Implementing Deconstruction in Florida: Materials Reuse Issues, Disassembly Techniques, Economics and Policy
|Charles J. Kibert
University of Florida
M.E. Rinker Sr. School of Building Construction
Powell Center for Construction and Environment
Fine Arts C 101
PO Box 115703
Gainesville, FL 32611
|Jennifer L. Languell
University of Florida
M.E. Rinker Sr. School of Building Construction
Powell Center for Construction and Environment
Fine Arts C 101
PO Box 115703
Gainesville, FL 32611
(352) 392-9029 June 14, 2000
Florida Center for Solid and Hazardous Waste Management
This work was funded by the Florida Center for Solid and Hazardous Waste Management and executed with the cooperation and support of the staff of the Powell Center for Construction and Environment.
Project Title: Implementing Deconstruction in Florida: Material Reuse Issues, Disassembly Techniques, Economics and Policy.
Principal Investigator: Charles J. Kibert, Ph.D, PE
Co-Principal Investigator: Bradley Guy, B. Arch
Principal Author: Jennifer L. Languell
This report would not be possible without the input and coordination of Dr. Charles Kibert and the Powell Center for Construction and Environment staff members, Dr. Abdol Chini, Alejandra Biaz, Bradley Guy, Sean McLendon and Kevin Ratkus.
The information contained in Chapter 9 – Deconstruction steps was make possible by a grant from the Florida Department of Environmental Protection and an Alachua County Innovative Recycling Project grant. The Powell Center for Construction and Environment conducted this study with the assistance of Kevin Ratkus acting as Field Supervisor, Sean McLendon and Bradley Guy were responsible for the collecting and interpretation of the project information.
Table of Contents
1 ABSTRACT…………………………………………………………………………………………………. v
2 EXECUTIVE SUMMARY………………………………………………………………………….. vii
3 INTRODUCTION…………………………………………………………………………………………. 1
3.1 Deconstruction Defined…………………………………………………………………………. 1
3.2 Sustainability……………………………………………………………………………………….. 1
4 WASTE IMPACT OF THE CONSTRUCTION INDUSTRY……………………………. 5
4.1 General………………………………………………………………………………………………….. 5
4.2 Current Practices………………………………………………………………………………….. 6
4.3 Waste Statistics……………………………………………………………………………………. 9
4.4 Potential Building Stock for Deconstruction……………………………………… 10
4.5 Recycling Limitations – The need for Decosntruction………………………….. 11
4.6 Florida…………………………………………………………………………………………………. 15
4.7 Summary………………………………………………………………………………………………. 20
5 DECONSTRUCTION BENEFITS……………………………………………………………….. 21
5.1 Social Benefits…………………………………………………………………………………….. 21
5.2 Economic Benefits………………………………………………………………………………… 22
5.3 Environmental Benefits……………………………………………………………………….. 23
5.4 Summary………………………………………………………………………………………………. 27
6 ESTABLISHING DECONSTRUCTION…………………………………………………….. 29
6.1 General………………………………………………………………………………………………… 29
6.2 SuPCCEssful Implementations………………………………………………………………… 29
6.3 Influence Factors………………………………………………………………………………… 31
6.4 EnvironmentAL Policy and Incentives………………………………………………….. 39
6.5 Barriers to Establishment…………………………………………………………………… 45
6.6 Summary………………………………………………………………………………………………. 47
7 USED BUILDING MATERIALS…………………………………………………………………. 49
7.1 Salvaged Quantities……………………………………………………………………………. 49
7.2 Used Building Material Associations…………………………………………………… 50
7.3 Markets and Resale…………………………………………………………………………….. 51
7.4 Wood Reuse………………………………………………………………………………………….. 53
7.5 Salvaged Wood Properties and Re-Grading…………………………………………. 55
7.6 Trends………………………………………………………………………………………………….. 58
7.7 Summary………………………………………………………………………………………………. 58
8 DECONSTRUCTION COSTS……………………………………………………………………… 59
8.1 Case Studies…………………………………………………………………………………………. 60
8.2 Cost Factors……………………………………………………………………………………….. 63
8.3 Labor cost and availability………………………………………………………………… 64
8.4 Summary………………………………………………………………………………………………. 65
9 DECONSTRUCTION STEPS………………………………………………………………………. 67
9.1 Permitting Process……………………………………………………………………………….. 67
9.2 Building Assessment – Building material inventory……………………………… 67
9.3 Environmental Assessment………………………………………………………………….. 68
9.4 Field Safety………………………………………………………………………………………….. 73
9.5 Workers Compensation Insurance……………………………………………………….. 74
9.6 Scheduling……………………………………………………………………………………………. 74
9.7 Jobsite Preparation……………………………………………………………………………… 74
9.8 Site Map of Deconstruction Field Organization……………………………… 74
9.9 Dismantling techniques……………………………………………………………………….. 85
9.10 Summary…………………………………………………………………………………………… 85
10 LESSONS LEARNED………………………………………………………………………………. 86
10.1 Establishing Deconstruction………………………………………………………….. 86
10.2 Deconstruction Process……………………………………………………………………. 87
10.3 Materials…………………………………………………………………………………………. 88
10.4 Markets……………………………………………………………………………………………. 88
11 DESIGNING FOR DECONSTRUCTION…………………………………………………. 91
11.1 Dibros Corporation…………………………………………………………………………… 92
11.2 Components of a Dibros Home…………………………………………………………… 92
11.3 Foundation systems and Flooring…………………………………………………….. 93
11.4 Framing…………………………………………………………………………………………….. 94
11.5 Wall Finishes…………………………………………………………………………………….. 95
11.6 Roofing……………………………………………………………………………………………… 95
11.7 Siding………………………………………………………………………………………………… 96
11.8 Design for Deconstruction – Recommendations………………………………… 97
12 CONCLUSION………………………………………………………………………………………… 99
13 RECOMMENDATIONS………………………………………………………………………… 103
LIST OF FIGURES
Figure 1 Waste Management Hierarchy………………………………………………………………………….. 3
Figure 2 Construction and Demolition waste categories……………………………………………………… 9
Figure 3 National Tipping Fee Trends………………………………………………………………………….. 14
Figure 4 State map containing high, low and average tipping fees……………………………………….. 17
Figure 5 Florida Population 1900’s through present………………………………………………………… 32
Figure 6 Florida Regional Planning Councils………………………………………………………………….. 42
Figure 7 Collection of sample for asbestos content test……………………………………………………. 71
Figure 8 Wall sample collection…………………………………………………………………………………… 72
Figure 9 Paint collection for lead level test…………………………………………………………………….. 72
Figure 10 Diagram of deconstruction field organization…………………………………………………….. 74
Figure 11 Removed interior trim………………………………………………………………………………….. 76
Figure 12 Interior wall surfaces removed……………………………………………………………………… 76
Figure 13 Removal of roofing material………………………………………………………………………….. 77
Figure 14 Exposed roofing structure…………………………………………………………………………….. 78
Figure 15 Stud wall skeleton after removal of roof………………………………………………………….. 78
Figure 16 Exterior stud wall ………………………………………………………………………………………. 79
Figure 17 Retrieval of studs from walls…………………………………………………………………………. 80
Figure 18 Flooring removal………………………………………………………………………………………… 80
Figure 19 Exposed joists……………………………………………………………………………………………. 81
Figure 20 Cutting floor joist free for recovery………………………………………………………………… 82
Figure 21 Pushing over chimney………………………………………………………………………………….. 82
Figure 22 Removal of mortar from bricks……………………………………………………………………… 83
Figure 23 Reclaimed dimensional lumber………………………………………………………………………. 84
Figure 24 Reclaimed larger dimension lumber………………………………………………………………… 84
LIST OF TABLES
Table 1 lists the tons produced by each waste category…………………………………………………… 10
Table 2 National Regional Tipping Fees……………………………………………………………………….. 13
Table 3 Sample tipping fees ………………………………………………………………………………………. 15
Table 4 Florida landfill regional locations………………………………………………………………………. 16
Table 5 Florida regional average tipping fees for C&D disposal………………………………………… 16
Table 6 Florida Counties with high tipping fees and corresponding recycling facilities…………….. 18
Table 7 Population and Waste, Florida…………………………………………………………………………. 19
Table 8 Florida C&D waste as a percentage of the total waste stream……………………………….. 19
Table 9 Deconstruction project recovery rates……………………………………………………………….. 24
Table 10 Waste Stream Percentages ………………………………………………………………………….. 43
Table 11 Highest cost items in the Dibros home……………………………………………………………… 93
Deconstruction is defined as the disassembly of structures for the purpose of reusing the structures components and building materials. The primary intent is to divert the maximum amount of building materials from the waste stream. Deconstruction is a relatively new term used to describe an old process – the selective dismantlement or removal of materials from buildings instead of demolition. The common practice in the industry is to cherry pick – strip out highly aPCCEssible recyclable, reusable or historic materials – prior to traditional demolition. (Traditional demolition usually involves mechanical demolition, often resulting in a pile of mixed debris, which is sent to a landfill). Deconstruction encompasses a thorough and comprehensive approach to whole building disassembly (versus cherry picking specialty items), allowing the majority of the materials to be salvaged for reuse.
The process of deconstruction can significantly decrease the national solid waste burden placed on the environment the construction industry. Through deconstruction, natural resources are saved, employment and training opportunities arise, and local businesses grow from using the materials diverted from the landfill. Deconstruction provides useful building material stock to building material yards, recycling centers and remanufacturing enterprises, which create additional jobs and community revenue.
Out of 260 million tons of non-industrial waste produced nationally each year, 136 million tons are a result of the construction and demolition (C&D) industry. This equates to approximately 33% of the waste produced nationally. Similar circumstances exist internationally, for example, in the Netherlands over 70% of the waste is a result of the construction and demolition industry and in Ontario approximately 20% of the total waste stream may be attributed to C&D. Similarly in the State of Florida, the Florida Department of Environmental Protection (FDEP) reports approximately 23% of the waste produced is a result of the construction and demolition industry. Deconstruction provides an excellent opportunity to target a significant portion of the waste stream for reduction.
This report investigates and analyzes the feasibility of replacing demolition and disposing of building materials with deconstruction and reuse. The report contains information from an extensive review of case studies from international and domestic regions. The examination of case studies resulted in the development of a list of influence factors affecting the implementation of deconstruction. Factors such as: labor, scheduling and cost, tipping fees at construction and demolition landfills, hazardous materials management, existing markets, value adding and marketing of reused materials, material grading systems, time and economic constraints, contractual agreements, environmental building goals, and public policy all affect the suPCCEssful implementation of deconstruction. These influence factors were further explored to provide insight into the feasibility of establishing deconstruction in the State of Florida.
OBJECTIVES: The project objectives focus on analyzing the feasibility of replacing demolition and disposal of building materials with deconstruction and reuse in the State of Florida. Deconstruction is defined as the disassembly of structures for the purpose of reusing components and building materials. The primary intent is to divert the maximum amount of building materials from the waste stream. Deconstruction is a new term used to describe an old process – the selective dismantlement or removal of materials from buildings instead of demolition. The common practice in the industry is to “cherry pick” or strip out highly aPCCEssible recyclable, reusable or historic materials – prior to traditional demolition. (Traditional demolition usually involves mechanical demolition, often resulting in a pile of mixed debris, which is sent to a landfill). Deconstruction encompasses a thorough and comprehensive approach to whole building disassembly (versus cherry picking specialty items), allowing the majority of the materials to be salvaged for reuse.
The process of deconstruction can significantly decrease the national solid waste burden placed on the environment the construction industry. Through deconstruction, natural resources are saved, employment and training opportunities arise, and local businesses grow from using the materials diverted from the landfill. Deconstruction supplies useful building material stock to building materials yards, recycling centers and remanufacturing enterprises, which create additional jobs and community revenue.
METHODOLOGY: The Powell Center for Construction and Environment at the University of Florida conducted an extensive search of case studies from international and domestic regions. The case study review allowed the Center to develop a list of influence factors affecting the implementation of deconstruction. These factors include: labor, scheduling and cost, tipping fees at construction and demolition landfills, hazardous materials management, existing markets, value adding and marketing of reused materials, material grading systems, time and economic constraints, contractual agreements, environmental building goals, and public policy all affect the suPCCEssful implementation of deconstruction. The Center further investigated regions in the United States that have achieved the suPCCEssful implementation of deconstruction. The investigations were augmented by visits to the West Coast and North Carolina. The West Coast has several regions such as the San Francisco Bay area and the Metro Portland area which have suPCCEssfully implemented deconstruction. Using these case studies as guidelines, the Center began an analysis of conditions in the State of Florida.
RATIONALE: Significant economic and environmental opportunities can evolve from better management of construction and demolition (C&D) waste components in Florida. This research project will report on technical, economic, and policy issues related to deconstruction, and will determine the constraints, opportunities, and procedures involved in establishing building deconstruction with the intent to salvage building materials for reuse in Florida. At present, approximately 23% of the municipal solid waste created in the State of Florida may be attributed to C&D waste (FDEP, July 1999). The US EPA reports that 92% of C&D waste is a result of renovation and demolition (Franklin Associates, 1998). With only 8% of C&D waste being generated from new construction, significant waste reduction opportunities arise from the renovation and demolition market-share. Reuse of reclaimed building materials is an under-investigated and rarely implemented strategy for waste reduction. SuPCCEssfully salvaging these materials can greatly reduce Florida’s resource and energy consumption, land use, groundwater degradation, and disposal costs while increasing employment opportunities for low-skilled workers and stimulating local economic activity.
The environmental impacts of demolished structures and their associated economic losses can be diminished through targeted materials reuse. Salvaged items can become value-added products through reuse or recycling with minimal added energy inputs. Lack of a recovery, reuse, and recycling infrastructure contributes to excess waste and environmental degradation. Implementing recovery and reuse will ultimately lessen the solid waste management burden and reduce environmental degradation. For example, the major impediments to the reuse of salvaged wood for structural applications include the lack of an existing grading system for recovered wood and minimal data on extraction and reprocessing costs. Evaluating the economics of regrading used wood products is critical to extracting maximum economic value from salvaged wood. Field research with stakeholder input (deconstruction and reuse companies, architects, builders, regulators, code enforcement, institutional users) will enable an understanding of the economics, and the technical and practical considerations underlying the use of salvaged building materials for private and commercial applications
Several case studies from the US and Canada prove that deconstruction is an economically and ecologically viable option to demolition and subsequent landfilling. In Florida, relatively low tipping fees and high rates of growth and development have contributed to the magnitude of C&D waste generation. In 1992 it was estimated that one seventh of all US C&D landfills were located in this State (Hanrahan, 1994). Assessing the deconstruction market and analyzing its potential market-share within the State of Florida will aid in reducing Florida’s solid waste management burden and its many associated problems.
The current population of the State of Florida ranks the State as the 4th most populous in the US Florida is projected to be the 3rd most populous State by the year 2025. Each year the State needs an additional 800 miles of new roads and constructs 730 new classrooms. Also required are additional water and sewer systems, prisons, courts, fire and emergency rescue, and other infrastructure services. This growth has costs, especially to the natural environment. Every day 450 acres of forest and 410 acres of farmland are cleared in the State. To sustain Florida’s population growth – new infrastructure – schools, homes, roadways and common amenities are needed. The growth of the State itself pushes the construction industry to provide infrastructure, which in turn increase in C&D waste. The Florida Department of Environmental Protection (FDEP) reports that construction and demolition waste is approximately 23% of the total waste stream.
In 1994, Florida had more landfills than any other state. Out of the nation’s 1,900 landfills, Florida was home to 280. This number has dropped to 163 as of November 1998. The decreasing number of C&D landfills is not a Florida specific phenomenon, but a result of increasing state and national regulations. The regulations will probably continue to become more vigorous – Florida’s population will continue to rise – and land will continue to be in demand. All of these factors can assist in the implementation of deconstruction since deconstruction reduces the amount of waste sent to landfills, slowing the rate the landfills will fill and prolonging their lives.
Encouraging revitalization and redevelopment of older communities can provide significant savings for local and regional governments while providing an environment conducive to the implementation of deconstruction. Sprawling development requires more roads, longer sewer lines and other infrastructure to serve it. The process of infill – versus sprawling development could assist in promoting deconstruction since it often requires renovation. As virgin property disappears, developers will look to demolition and renovation of outdated structures to support the influx of new residents.
SuPCCEssfully salvaging materials through deconstruction can greatly reduce Florida’s resource and energy use, land consumption, groundwater degradation, and disposal costs while increasing employment opportunities for low – skilled workers and stimulating local economic activity. The environmental impacts of demolished structures and their associated economic losses can be diminished through targeted materials reuse. Lack of a recovery, reuse, and recycling infrastructure contributes to excess waste and environmental degradation. Implementing recovery and reuse will ultimately lessen the solid waste management burden and reduce environmental degradation. In addition the implementation of deconstruction allows Florida to continue experiencing growth while not compromising the quality of life experienced by existing and future residents. Deconstruction will also create new industries to support further economic growth.
RESULTS AND CONCLUSIONS: Preliminary investigation has shown some regions in the State have conditions very similar to that of San Francisco (a region where deconstruction is thriving). For example, three South Florida coastal metro areas rank in the top 20 nationally in per capita income. The West Palm Beach – Boca Raton metropolitan area, ranks the highest in Florida and third in the nation, the Naples area ranks seventh nationally and the Sarasota-Bradenton area is 16th. With similar incomes, these regions also experience high growth rates and have a higher density than non-coastal regions of the State. Other potential regions that are likely candidates for implementing deconstruction are the Tallahassee, Pensacola, and Jacksonville areas. These are larger established cities, which are old enough to have some aged building stock which could support deconstruction. Although beyond the scope of this project, the Center intends to further investigate and visit these regions to determine implementation feasibility. Contact with these regions will be augmented by visits to discuss specific local policies and identify local resources such as salvage and reuse businesses. In addition to further analysis of the State of Florida, the Center will create training manuals and training sessions based on the findings from this project.
3.1 Deconstruction Defined
Deconstruction is defined as the disassembly of structures for the purpose of reusing components and building materials. The primary intent is to divert the maximum amount of building materials from the waste stream. Top priority is placed on the direct reuse of materials in new or existing structures. Immediate reuse allows the materials to retain their current economic value. Materials that are not immediately reused can be recycled, downcycled, or upcycled. Examples of these processes are the immediate reuse of large structural timbers reclaimed and used as structural members of a new building. Recycling materials would consist of turning scrap steel into new steel rebar or beams. Downcycling for example would be turning a concrete slab into road base, where upcycling would consist of salvaging lumber and creating custom cabinetry or other value-added products.
Deconstruction is a new term used to describe an old process – the selective dismantlement or removal of materials from buildings instead of demolition. The common practice in the industry is to cherry pick or strip out highly aPCCEssible recyclable, reusable or historic materials – prior to traditional demolition. (Traditional demolition usually involves mechanical demolition, often resulting in a pile of mixed debris, which is often sent to the landfill). Deconstruction encompasses a thorough and comprehensive approach to whole building disassembly (versus cherry picking specialty items) allowing the majority of the materials to be salvaged for reuse.
Deconstruction requires the careful disassembly of buildings in the reverse order of construction. Deconstruction, unlike demolition, is labor intensive, generally low-tech and environmentally sound. The process of deconstruction can significantly decrease the national solid waste burden the construction industry places on the environment. Through deconstruction, natural resources are saved, employment and training opportunities arise, and local businesses grow from using the materials diverted from the landfill. Deconstruction supplies useful materials to building materials yards, recycling centers and remanufacturing enterprises, which create additional jobs and community revenue.
Before discussing the concept and principles surrounding sustainability, it is necessary to first define the meaning of sustainable development. As defined in the Brundtland Report sustainable development is “…meeting the needs of the present without compromising the ability of future generations to meet their needs…” The development experienced on local, regional, and national levels plays a key role in society’s sustainability. The changing demands of society must be taken into consideration, and projections must be made about society’s future needs at local, regional, and global levels. Without foresight, future needs and demands cannot be met. Researchers’ assumptions based on society’s inputs are used to predict future priorities. The primary concerns may be energy, resource conservation, or solid waste management. Projecting the national, regional, and local future growth will direct the efforts in creating a sustainable environment and establishing conservation goals for the construction industry.
Once the goals for sustainable buildings are established, these goals and concepts must be incorporated into the design of buildings. With the appropriate parameters, design teams can begin to think “outside of the box” and break away from traditional building techniques. Traditional building techniques are proven, but far from sustainable. Our nation has an environmental responsibility to continuously make improvements on the construction, renovation, and demolition process. One such sustainable improvement is deconstruction.
A key element in designing for the environment is staying focused. What is built and how it is built has social repercussions, economic impacts and ecological effects (Building with Value, EPA, 1993). Resource use and environmental degradation have always been an unavoidable part of human existence. It is important that design professionals and other members of the building construction industry aPCCEpt and remain collectively focused on remaining committed to preserving the environment. This development process requires transcending professional boundaries between architects and engineering consultants and fostering a more effective dialogue among all participants involved in the production of buildings (Cole, 1996). Innovative environmental buildings reflect changes in both the process and their creation, as well as their distinctively different design features and characteristics. Environmentally responsible building design involves challenging existing design norms and promoting a shift in attitude to embrace new ways of thinking about the processes of production, use, and disposal of a building.
Changing environmental policy and attitudes have fostered new developments in solid waste management and environmental preservation. The construction industry’s practice of land-filling construction and demolition debris not only results in a significant loss of potentially reusable building materials but also wastes natural resources and landfill space. The effective reuse and recycling of materials requires at least three key elements: knowledge, incentives, and coordination. Deconstruction is considered a new strategy to advance local and regional sustainability and reduce environmental degradation. Deconstruction is a significant advance toward a sustainable environment. The immediate reuse of materials keeps existing materials in circulation and out of landfills.
In looking at the waste management hierarchy (Figure 1) it can be seen that one of the highest levels is reuse. However, the majority of the current practices fall in the lower two levels. The common practice on construction and demolition sites is to simply toss “waste” into the dumpster. This practice often occurs regardless of the potential value of the materials. In less developed areas debris is burned on site – often without permits or authorization. Efforts do exist on a recycling level, however as discussed later these efforts alone will not create a sustainable future. Deconstruction assists in moving the construction industry further up the sustainability “food chain”. Not only does deconstruction conserve landfill space, but it can reduce the demand for new materials, decreases the environmental strain caused by the mining of raw materials and preserves the original energy spent in the creation of building materials.
In regions lacking natural resources it is commonplace to reuse the supplies on hand. Structures such as old homes, barns, and buildings are used to build new or needed facilities. Regions lacking natural resources turn to locally available materials, whether they are new or borrowed materials to sustain their new construction. However the drive to reuse these materials is not limited to the lack of natural resources – it is basic common sense. Reclaimed or salvaged building materials are inherently valuable simply based on the energy and raw materials used to create them. Dismantling a building into its building components keep the materials in service as long as possible. Keeping materials in service longer results in reduced demolition or restoration waste, which in turn preserves landfill space. There is no additional energy spent mining new resources or manufacturing new products. Immediate reuse of materials also keeps valuable usable materials such as dimensional lumber from being downcycled into items such as oriented strand board, particleboard or mulch – a less valuable products. Although this is better than landfilling the materials, immediate reuse provides the best conservation of materials and energy. In addition to the many environmental benefits, deconstruction also has many positive social and economic implications.
There are many factors that can influence the suPCCEssful implementation of deconstruction. Factors such as: labor, scheduling and cost, tipping fees at construction and demolition landfills, hazardous characteristics of demolition waste, markets, material grading systems, time and economic constraints, contractual agreements, and public policy. These conditions affect the potential for deconstruction to develop into a long term, economically viable sector of the construction industry for waste reduction, resource conservation, and job creation.
Waste Impact of the Construction Industry
4.1 General Buildings
have a significant impact on the environment. In the United States, buildings represent more than 50 % of the nation’s wealth. New construction and renovation account for approximately $800 billion or approximately 13 % of the Gross Domestic Product and employ over 10 million people (Sustainable Building Technical Manual, 1997). The construction industry uses 40% of all extracted materials. Thirty percent of all energy used is a result of the construction industry and the built environment (Franklin Associates, 1998). Out of the 395 million tons of waste produced nationally, 135 million tons are a result of construction and demolition (C&D) waste. Over one-third of the waste produced in the nation is a result of one giant industry. Approximately 7 pounds of waste is produced for every square foot of new construction. Renovation and demolition produce up to 70 pounds of waste per square foot. It is clear, based on these numbers, that there is significant room for improvement in the way the industry operates. Buildings are constructed, and on average, are demolished twenty-eight years later (Bohlen, 1997). Unfortunately traditional demolition is with a wrecking ball leaving piles of mixed debris (Lerner, 1997). The construction industry lags far behind other industries in efficiency related to materials consumption, reuse, and recycling. For example, a new automobile such as the BMW contains 70 percent recycled content, but a new building probably contains less than 1 percent reclaimed materials (Stamcampiano, 1999).
The total economic and environmental impact of the construction industry begins with raw material extraction and continues to product manufacturing, product transportation, building design and construction, operations and maintenance, and building reuse or disposal. Each building product alone contains vast quantities of energy – energy used to extract raw materials, process and create a marketable product. Extraction of these natural resources, especially through mining and smelting, is one of the most wasteful, energy intensive and polluting industries on earth. Reusing and recycling building materials prevents this pollution by reducing the need for virgin natural resources to be mined and harvested, while saving already threatened forests and natural areas from further degradation. When you consider the combined energy required to transport materials and the labor required to design and construct buildings, demolishing a structure is simply throwing away many valuable resources. Reusing building materials conserves this energy “embodied” in the products, meaning we are conserving the energy originally used in the manufacturing and transportation of these materials. Deconstruction is a mammoth step toward sustainability. Salvaging the materials from structures reduces waste, preserves the energy originally used to create the materials, and lessens the need for virgin materials. For example, reusing wood eliminates the harvesting, transporting, processing and other energy intensive steps that would be needed to produce new dimensional lumber. Rather than smashing the value of these salvageable materials into pieces and burying the materials in a landfill, reusing and recycling keeps the material value within the local economy where it can continue to produce financial benefits as it is remanufactured and used again.
4.2 Current Practices
In the movement toward sustainability there are several changes occurring in the construction industry. There is a movement toward using “green” materials, more energy efficient structures, managing construction waste, and implementing reuse and deconstruction. Unfortunately, the construction industry, as most industries are, is driven by money. This industry is well-established and, for the most part, highly resistant to change. The industry as a whole feels comfortable and confident in their tried and true methods. When it comes to “debris” or “waste” the industry prefers the easiest, fastest, and cheapest option, which in most parts of the nation is landfilling. The industry also perceives materials that are delivered to the site not wrapped in visqueen® and on wooden pallets to be sub-standard. These are the perceptions that must be changed – there are other waste management options and there are other sources of materials. Although the focus of this report is reuse and deconstruction, it is important to mention these sustainable factors, as they are an integral part of the construction industry progress.
The current practice in industry is to landfill most materials perceived as waste. The large quantities of debris also contribute greatly to the cost increase felt by solid waste management. Landfills have limited space and therefore can only receive a limited amount of trash. When one landfill fills, it must be replaced by another landfill, which is generally more expensive to operate and maintain. The higher cost is a result of complying with environmental regulations, higher expenses in siting a new location, buying or allocating land, constructing the landfill, operating expenses, and long term maintenance costs after the landfill is closed. Additionally, the new landfill may be further away than the old landfill, increasing transportation cost.
In general, it costs more to build a new landfill than to maintain an existing one. Paying the higher cost at a new landfill and paying the increasing cost of closing a landfill are avoided by keeping the old landfill open. Under new Federal regulations governing landfill closure, landfills must be monitored, inspected, and maintained for at least 30 years following the facility closure. This includes operation of the leachate collection system, extensive ground water monitoring, inspection and repairs as needed of the cap and other protective systems, and the maintenance of the financial assurance bond or other security. Closing landfills and the costs associated with this process are extraordinary. For example, the West Marin Sanitary Landfill in California expects its closing cost alone to be upward of $2.5 million.
The bottom line is that landfills are becoming increasingly expensive. In some way, society is paying these costs – through tipping fees or taxes. The EPA has written and the DEP has adopted guidelines for the full cost accounting of landfills. These guidelines should be reviewed as they take into consideration many underlying costs associated with the landfilling of debris. No neighborhood welcomes the thought of having a new landfill built in their backyard. Keeping existing landfills operating as long as possible benefits both the environment and society. To extend the longevity of the landfills, increasing waste reduction and recycling efforts are a must and deconstruction can significantly reduce the amount of usable materials sent to landfills. Deconstruction case studies have shown waste diversion rates as high as 90%. Recovery rates are further discussed in Chapter 5.
Longevity is central to environmentally responsible building design (Cole, 1996). Longevity can be increased by adaptive reuse rather than new construction, or longevity can relate to the building components through increased recycling and the use of salvaged materials. The common aim of each is to keep materials within the materials cycle as long as possible without the need for further processing. Renovation provides longevity of the structure itself if it is designed properly. Although the interior is often completely lost, the potential to reuse the skeleton of the building exists. Consideration of longevity points to the importance of distinguishing between strategies that result in immediate environmental benefits from those when the benefits are deferred to the future. Significant waste savings can result from reusing the structure of a building. Designing for adaptability of interior spaces could reduce the need for complete renovation of the interior of structures.
The cost of renovation is 15-20 percent higher per square foot (sf) than the cost of new construction. For example, on a typical commercial project, the cost of new construction is approximately $100/sf, where the cost of renovating a structure is approximately $118/sf. It is possible to design adaptable buildings, therefore reducing the cost of renovation. Adaptable building design makes altering the structure more appealing than simply demolishing structures for the needed land. Renovating is the ultimate reuse of a space, if done properly, few new materials are needed and the bulk of the structure remains intact. The highest level of adaptability is deconstruction. If a structure can completely be disassembled and reassembled into a new needed structure, the structure has shown complete adaptability.
Refurbishing older buildings involves both the residential and commercial sectors. Large-scale renovations and adaptive reuse conversions are common in Canada. For example, in Quebec City, a church has been converted into condominiums; in Ottawa, a school into a regional building; in Toronto, the Bank of Montreal into the Hockey Hall of Fame; in Winnipeg, industrial buildings into seniors’ housing; in Edmonton, the former Lieutenant Governor’s mansion turned into a museum; and in Vancouver, offices were refitted for use by the University of British Columbia (Construction Waste Audits, 1999). In many cases the adaptive reuse conversion option presents the most cost-effective and practical means to preserve historical buildings. Although restoration creates a potentially significant waste stream from the typical “gutting” of the interior of a building, if deconstruction were implemented, many materials would be salvaged, reused, and diverted from the waste stream. More importantly, considerably less demolition waste is created in renovation since the shell of the building remains intact.
4.2.3 Green Building Materials
On an environmental level, there is a choice between using “green” materials in the construction of buildings and designing buildings as potential sources of future resources (raw materials) for new buildings. One must address the issue that green building materials are not always the best choice when designing a building for deconstruction. The ideal choices for deconstructable building materials are those with the greatest service life and those materials that are desirable or hold historical value. In order for the concept of deconstruction to be effective, it is necessary to use materials that will be in great demand in the future. For example, linoleum floor such as Marmoleum®, is made from renewable raw materials. The flooring contains linseed oil, wood and cork flours, natural rosins, crushed limestone, and non-toxic pigment (E Build, 1997). This flooring is a much “greener” product than a traditional vinyl floor covering, however holds little future value. If a traditional solid wood tongue and groove floor was installed, the floor would last much longer and retain its value over time. The tongue and groove floor is worth salvaging, where as the linoleum floor is basically disposable.
Use of deconstructed building materials can offer financial benefit and positive environmental ramifications. Considerations must be given to energy and water efficiency, waste reduction, construction cost, building maintenance and management savings, insurance and liability, employee health and productivity, and building value. In addition, it is important to consider the local economic development potential of green building initiatives and present methodology for environmental life-cycle assessment and its application to green buildings.
The movement to “green” materials has begun as consumers find themselves more informed about environmental degradation. One may assume that economic and regulatory issues will create changes within the material industries, however the creative design which makes the best possible use of materials both individually and in combination, will remain in the domain of the designer and builder.
The primary reasoning for demolishing structures is based on the needs of society – supply and demand. There is ultimately a demand for the structure to be removed. This demand can be a result of a need for the land an existing building occupies, the building may no longer serve any of society’s needs, (for example old mill type factories), or the building may no longer be structurally sound. These are all opportunities to salvage existing resources. Demolition is a fast seemingly inexpensive society answer for structure removal.
Some deconstruction exists in today’s market and deconstruction for the reuse of lumber is fairly common. Nationally, deconstruction (as opposed to demolition) occurs to some extent on approximately 40% of all demolition sites over 20,000 square feet (Jefferson Recycled Woodworks, 1997). Although this figure includes buildings that are only partially deconstructed, the shift toward salvage and reuse is beginning. There is only one true reason for the shift – money. Although we would like to believe that society and industry is changing purely to benefit and preserve the environment, this is not a reality. Demolition contractors have made money from used wood in ways that were not possible ten to fifteen years ago. In some regions, tipping fees are rising enough that contractors notice the cost of waste disposal. Unfortunately, often increasing the disposal cost is the only way to make more of the industry look for alternatives such as deconstruction. In addition to cost, another barrier to deconstruction is the possibility of hazardous materials. The majority of the homes that are good candidates for deconstruction contain asbestos and lead. By law, these materials can not be reused and must be disposed of as hazardous materials, a more costly alternative than traditional disposal.
4.3 Waste Statistics
4.3.1 Quantities and Components
Constructing, renovating, and tearing down commercial buildings nationwide produced approximately 136 million tons of waste in 1996 (Franklin Associates, 1998). Figure 2 provides pie charts to show the component breakdown of the construction and demolition waste stream based on Environmental Protection Agency composition breakdown of the C&D waste stream. Table 1 shows the actual quantities of C&D debris based on source of the waste. It is estimated that 65 million tons (48 percent) of the 136 million tons were a product of the demolition of structures. The remaining 71 million tons of the C&D waste stream is comprised of approximately 60 million tons (44 percent) renovation waste and 11 million tons (8 percent) new construction waste. Further analysis of the demolition portion of the waste stream reveals that 45 million tons (69 percent) of the 65 million tons is a result of the demolition of residential structures. The remaining 20 million (31 percent) of the 65 million is a result of the demolition of non-residential structures.
These numbers indicate that the majority of the C&D waste stream is a result of demolition and renovation (92%) – 125 million tons of waste – and not new construction. This significant percentage of the waste stream can be directly impacted – reduced – by deconstruction. Renovation requires partial or complete removal of the interior and possibly exterior of the structure prior to the new construction that occurs to renew the structure. During the “rip out” stage of renovation deconstruction could significantly reduce waste. Targeting the demolition and renovation waste stream provides the greatest potential impact for reducing the amount of usable building materials that are commonly sent to landfills. Since these activities account for the majority of the C&D waste, the focus should be on providing alternatives to traditional demolition. Both demolition and renovation provide opportunities for material recovery, reuse and recycling by means of deconstruction.
Deconstruction substantially increases the amount of demolition material reused or recycled by placing priority on recovering materials for use in new construction and manufacturing enterprises. Several case studies have shown the average rate of materials recovery for deconstructed buildings is 80%. The case studies reported findings of recovery rates varies between a minimum of 50% to a maximum of 90%.
Several deconstruction demonstration projects have been completed showing that high diversion rates may be achieved. The NAHB Research Center completed the deconstruction of a two-story, four-unit apartment building in Maryland (NAHB, 1997). The Research Center measured the volume and the weight of all materials on site, whether salvaged, recycled, or landfilled. The diversion rate was 76 percent by weight and 70 percent by volume.
4.4 Potential Building Stock for Deconstruction
Every year as many as 300,000 buildings are demolished in the United States (NAHB). On a national level there is not a shortage of structures that can potentially be deconstructed. The shortage occurs in the lack of infrastructure and incentives to support deconstruction activities. Over 100 million housing units exist in the US, most of which are wood-framed. Since the turn of the century, over 3 trillion board feet of lumber and timber have been sawn in the US, and much of it still resides in existing structures (Falk, 1999). Nationally, 7,000 units of public housing and over 100,000 privately owned homes are demolished each year. Many of these structures could be deconstructed, creating a supply of building materials for reuse/recycling versus adding of tonnage to the C&D waste stream. Opportunities for deconstruction exist in practically every community in the US. Virtually all houses constructed prior to World War II are candidates for deconstruction due to the quality of materials used and the methods used to construct them. (Hendricks, 1998).
4.5 Recycling Limitations – The need for Decosntruction
In an effort to reduce the solid waste management burden, attempts have been made to increase the recovery rate of C&D debris for recycling. The major barriers to increased recovery rates at this time are:
- The cost of collecting, sorting, and processing
- The low value of the recycled-content material in relation to the cost of virgin-based materials
- The low cost of C&D debris landfill disposal
4.5.1 Collecting, Sorting, and Processing
When debris is delivered mixed to a disposal facility, the current methods of collecting, sorting and processing construction waste materials leaves little room for improvement. Debris in the mixed state requires tedious and labor intensive separation. The best way to combat this sorting barrier is to separate out the usable material prior to them reaching the landfill, meaning the materials should not be mixed or lumped together only to have to be separated again. Deconstructing allows for each material to be separated at the source, eliminating dump trucks of mixed debris. Not only does deconstruction eliminate mixed debris, it allows for the immediate reuse of materials and facilitates easier recycling because you can see exactly what materials you have. It is important to note here that landfills often charge higher rates for mixed debris versus sorted debris. Deconstruction by nature creates sorted debris resulting in lower costs of disposal when material must be discarded.
4.5.2 Perception of low value
The perceived low value of recycled content materials is social, incentive, and subsidy driven. Without a change in societal attitude, recycled materials will continue to be viewed by the majority of society as substandard but environmentally friendly. The nation’s economy is, and always will be directed by incentives and subsidies. Subsidies for recycling efforts pale in comparison to the hundreds of billions of dollars in subsidies provided to virgin-resource processors over the past century and which continue today. The virgin-based forest products, mining, and energy industries all benefit from both direct and indirect subsidies and tax breaks. Some examples of these tax breaks and subsidies include percentage-depletion allowances, which are intended to promote resource exploration and below-cost timber sales from federal lands. Other subsidies include US Forest Service research donated to industry, write-offs for timber management and reforestation costs, and below-cost mining leases based on an 1872 law. These subsidies do not include the many exemptions from environmental laws that the virgin-resource industries enjoy, allowing them to externalize costly burdens to the environment. The government support needed should come in the form of marketing campaigns supporting recycling and salvaged materials for construction. This is especially beneficial as a source of low cost, high quality materials for low-income housing programs.
4.5.3 The Drive for Change – Landfill Information
The largest number of C&D recycling facilities were reported to be in the Western states (28 percent) and the Mid-Atlantic states (27 percent). The Southwest and Rocky Mountain States each have only three percent of the total recycling facilities and the Southeastern, Upper Midwestern and New England states have 12, 13, and 14 percent of the facilities, respectively. As stated in Waste Spec, Model Specifications for Construction Waste Reduction, Reuse, and Recycling there is a correlation between disposal costs (tipping fees) and the construction industry finding alternative outlets for their waste. The turning point for tipping fees lies around the fifty-dollar mark. In regions where tipping fees have approached the $50 per ton mark the contractors, workers, developers and owners are not only more open to waste disposal alternative, but businesses exist to offer alternatives. For example, in the San Francisco Bay area, there is an extensive network of businesses to support deconstruction activities. In this region tipping fees can be as high as $110.00 per ton (CIWMB, 1997). An integral network of businesses exists to support the salvage, sale, and reuse of lumber. In addition, due to this network structure, several businesses have developed which use these salvaged materials to create value-added products. This structure is explained further in Chapter 6 Establishing Deconstruction. This section also contains a comparison of regional influences.
An important analysis which has not been undertaken would be an in depth look at the San Francisco area waste stream composition and quantities pre and post the establishment of deconstruction. This analysis would allow quantification of the deconstruction effort on the reduction of the waste stream. It would be expected that the quantity of demolition waste in this region would significantly decrease.
A large fraction of C&D debris generated in the United States ends up in C&D landfills. Since much of this waste stream is inert, solid waste rules in most states do not require the landfills to provide the same level of environmental protection (liners, leachate collection, etc.) at C&D landfills as is required at landfills licensed to receive MSW. Therefore, C&D landfills generally have lower tipping fees, and handle the majority of the C&D debris. Several factors influence tipping fees. Additional environmental awareness, increases in regulations and restrictions, loss of land and natural habitat, and in general inflation. It is extremely unlikely that tipping fees will remain constant. Shown below in Table 2 are the average regional tipping fees throughout the nation. In each region there is a steady increase in the average tipping fee.
The regions contain the following states:
- Northeast – Connecticut, Maine, Mass., New Hampshire, New York, Rhode Island, Vermont
- Mid-Atlantic – Delaware, Maryland, New Jersey, Penn., Virginia, West Virginia
- South – Alabama, Florida, Georgia, Kentucky, Miss., North Carolina, South Carolina, Tenn.
- Mid-west – Illinois, Indiana, Iowa, Michigan, Minnesota, Missouri, Ohio, Wisconsin
- West Central – Colorado, Kansas, Montana, Nebraska, North Dakota, South Dakota, Utah Wyoming
- South Central – Arizona, Arkansas, Louisiana, New Mexico, Oklahoma, Texas
- West – California, Idaho, Nevada, Oregon, Washington
A few conclusions can be drawn when comparing regional tipping fees and the percentages of recycling facilities. As Waste Spec indicates, there tends to be a movement toward looking at alternative ways to handle waste when tipping fees approach $50.00. At first glance, we looked at the region with the highest percentage of recycling facilities – the west – with 28%. When comparing this 28% to the average tipping fees in the region we see the tipping fees are in the $30.00 range. With this region containing the most recycling facilities, we would expect the tipping fees to be much higher. However, in many areas on the West Coast, the tipping fees are above the $50.00 range and in these regions we see a concentration of recycling facilities. The states inland from the West Coast have reduced the tipping fee average. The West Coast is also traditionally known for its natural environment and remains at the forefront of environmental preservation. The next region – the mid-Atlantic region – there are 27% of the recycling facilities. In this region, we note the tipping fees are in the $60.00 range. This correlates exactly with the Waste Spec prediction. We look next at the Northeast, which also fits this prediction. Regions also following this trend are the central regions – combined only containing 6% of the recycling facilities with tipping fees well under the $20.00 mark.
The tipping fee trends shown in Figure 3 provide a graphical representation of the tipping fees throughout the nation. All regions of the nation are experiencing increasing tipping fees. The tipping fees in this graph are to the year 2010.
The most obvious observation from this graph is that the tipping fees are indeed rising nation wide. One EPA report indicates that tipping fees are rising at a rate greater than that of inflation. The report indicates a 7% rate of increase in tipping fees as compared to the general inflation rate that hovers around the 2% range. The tipping fees are rising fastest in the most populated areas – the Northeast, East Coast, and the West Coast. As would be expected, regions with high tipping fees have begun looking for alternatives to traditional waste disposal. We note that the majority of the case studies have occurred in these regions – California, Connecticut, Maryland, Oregon and Canada.
The regions approaching the fifty-dollar mark are the Mid-West and the South followed by the West and South Central states. Again, in the areas where the tipping fees have approached or exceeded the fifty-dollar mark, alternatives for traditional demolition have been identified and are being implemented. There is an underlying incentive for demolition contractors to identify other outlets for their waste. It is important to note here however, that although tipping fees are a significant driving factor, they are not the only influence factor in implementing change. Other influence factors such as regional issues, historical value, land scarcity and labor are discussed later in this report.
Looking at not only the cost of landfilling debris but also the location of landfills available for use is an important issue. A 1994 survey done for the EPA identified about 1,900 active C&D landfills in the United States (Sustainable Systems, 1994). It would be expected that regions with many acres available for new landfills and large numbers of existing landfills could offer lower tipping fees. This is indeed the case in Florida. Florida had the largest number (280) of the 1,900 landfills reported in 1994. This number has dropped to 163 as of November 1998. The decreasing number of C&D landfills is not a Florida specific phenomenon, but a result of increasing state and national regulations. The dropping number of open landfills should not be taken lightly. The regulations will continue to increase – Florida’s population will continue to rise – and land will continue to be in demand. All of these factors can assist in the implementation of deconstruction since deconstruction reduces the amount of waste sent to landfills. Reducing the waste prolongs landfill lives and reduces the need to construct future facilities.
In 1980, Florida had approximately 500 open dumps. During this time period, it was a common practice to either burn or use one of these open dumps in order to alleviate the solid waste. Not one of these landfills contained any methods to prevent toxins from leaching into the groundwater. The State of Florida in addition to the Municipal Solid Waste landfills has 163 active construction and demolition (C&D) debris disposal facilities. The table below shows their locations within the State. Of these facilities, 97 are permitted as active C&D disposal facilities and 71 are permitted as land clearing facilities. Five facilities are permitted as both C&D and land clearing facilities. Prior to 1996 Florida experienced a steady growth in the number of C&D facilities. Since 1996 there has been a significant drop in the total number of permitted C&D disposal facilities partially due to new C&D regulations.
The regional locations within the State of Florida are shown in Table 4. For simplicity the State was divided into the areas shown – these are the divisions used by the DEP (Department of Environmental Protection). These numbers show that the majority of Florida’s landfills are located in the northwest section of the State. The northwest section is closely followed by the central region with respect to C&D debris facilities. However, if the land clearing debris facilities are included, the northwest region contains approximately 2 ½ times the landfills contained in any other region of the State. The concentration of the landfills in the northwest and central portions of the State are primarily due to the mining industry. In addition to the mining industry, these sections of the State have a less dense population than coastal and southern areas of Florida. The mining industry left many open pits which the industry calls abandoned quarries. These quarries lend themselves perfectly to becoming landfills.
Although the average tipping fees throughout the State are fairly constant, some variation may be noted. Average tipping fees based on Florida regions are presented in Table 5. In general the highest tipping fees are in the southern portion of the State – which tends to be the most populated area. Tipping fees are somewhat lower in the north and central regions of the State where the cost of purchasing land for landfills tends to be less than that in more metropolitan areas to the south.
The highest tipping fee was found in Monroe County in the South region of the State with tipping fees of $92.00 per ton. The lowest tipping fee was found in Glades County where the fees are $5.00 per ton (FDEP, 1998). Figure 4 identifies these regions and shows the regional average tipping fees.
Although there are regions in the State where the tipping fees are higher than the nation’s average (approximately $44.50), for the most part the tipping fees throughout the State are low. As long as tipping fees remain low, there is little incentive for the construction industry to alter their traditional form of disposal – landfilling. In the counties with the highest tipping fees, we would expect to see alternatives, such as recycling facilities. When looking at the recycling facilities listed for the State (FDEP, 1998) there appears to be no correlation with tipping fees and location of recycling centers. This could be a product of the recycling industry’s volatility. As listed in the FDEP report there are a total of 51 recycling facilities in the State that aPCCEpt construction and demolition debris. However, not all of these recycling facilities aPCCEpt all types of C&D debris. Table 6 shown below lists the counties with tipping fees approaching or exceeding the $50.00 mark and the corresponding number of recycling facilities.
Only eight of the States 51 recycling facilities are located in the counties with the highest tipping fees. It would be expected that the recycling facilities would be focused in these areas, instead, the State has a fairly consistent spread of recycling facilities throughout its regions.
18.104.22.168 Population and Waste Comparison
When comparing the national waste stream and the Florida waste stream several differences are noted. There are differing methodologies between classifications for the EPA (national waste stream) and the FDEP (Florida waste stream). The EPA does not consider C&D debris part of the municipal solid waste where FDEP does. As reported earlier the EPA states that approximately 52% of the waste stream is C&D waste, when looking at the FDEP information, the C&D portion of the waste stream is approximately 23%. In the FDEP 1999 Solid Waste Management in Florida report indicates “Three types of Waste dominate Florida’s MSW stream: paper, yard waste, and construction and demolition debris”. These three components comprise an estimated 63% of the State’s MSW collected during 1997 on a weight basis. When compared to national waste consumption data, Florida’s MSW exhibits a relatively higher percentage of C&D debris and a significantly lower relative percentage of total paper. Historic waste composition data indicates that the percentages of each type of waste component have remained fairly constant with the exceptions of C&D debris and yard waste, both of which have increased (FDEP, 1998). This statement seems to indicate the primary discrepancy between the C&D national and Florida numbers are a result of waste category classifications and methodologies. Although no direct conclusive relation can be drawn, we can look at Florida’s population growth, total waste and C&D waste as shown in Table 7. The total waste in the table shows the Municipal Solid Waste (MSW and C&D waste combined. The Solid Waste Management Report does not specify if industrial waste is included. It should be noted that the MSW figures do not include industrial waste.
The current population of Florida ranks the State as the 4th most populous state. Florida is projected to be the 3rd most populous state by the year 2025. The growth rate of the State of Florida is approaching 2% per year while the National growth hovers around 1%. To sustain Florida’s population growth – new infrastructure – schools, homes, roadways and other common amenities are needed. The growth of the State itself pushes the construction industry to provide additional infrastructure which increases C&D waste. As seen in Table 6, Population and Waste, the rate of increase or growth rate of the population and the C&D waste do not correspond. The rate of increase of the C&D waste is significantly higher than the population growth rate. However when looking at the total growth of waste, the rate of increase is slightly less than the population growth rate. These numbers indicate the great influence that the construction industry has on the waste stream produced in the State.
Florida experiences both an increase in total waste and an increase in the percentage of total waste attributed to the C&D sector. As seen in Table 8, the C&D percentage of total Florida waste shows a steady increase.
According to the FDEP, C&D waste was 22.61, 23.12, and 23.1 percent of the total waste stream in 1995, 1996, and 1997 respectively. The FDEP has predicted that in 2017 the C&D waste stream will remain approximately 22.67 percent of the total waste stream. However when looking at these figures and using a calculated growth rate from historical data provided by the FDEP, the projected total waste expected in 2017 would be 28,024,267 tons and the corresponding C&D waste for the year 2017 would be 6,353,101 tons. Meaning that approximately 22.67% of the total waste would be a result of the construction industry. This percentage is exactly what the FDEP has indicated, however, the final quantities differ. The State shows 6,952,287 million additional tons of total waste and an additional 1,574,833 tons of C&D waste. This indicates the State is not assuming the future rate of growth for waste is similar to the historic growth. The State has assumed the rate of growth of waste is increasing. The importance of this fact is the State is aware of the rapidly increasing solid waste burden and they are projecting it to worsen. Since C&D waste is the largest single components of the total waste stream in Florida it becomes increasingly more important to target this portion of the waste stream for reduction. Especially since the majority of the waste stream is recoverable, reusable and recyclable.
Florida’s rapid population growth unfortunately is not uniform throughout the State. Popular coastal regions of the State are becoming more densely populated and land is being sold at a premium. As virgin property disappears, developers will look to demolition and renovation of outdated structures to support the influx of new residents. Implementing deconstruction prior to the need will provide deconstructors the time needed to master the task and beat the learning curve prior to a statewide shortage of landfill space.
APCCEptance of structures as non-permanent fixtures in society is a key to changing the waste produced by the industry. The construction industry in this nation produces over 136 million tons of waste each year. Based on our nations growth and more specifically the growth of the State of Florida, the C&D waste quantities will continue to rise. Relatively speaking, the majority of the waste produced is a result of the demolition and renovation sectors of the construction industries. While tipping fees remain low, financially there is little incentive for the construction industry to change traditional practices of landfilling what the industry perceives to be waste.
Florida’s rate of growth for C&D waste is approaching 3% while the population growth hovers just below 2%. In order to preserve the natural beauty of the State, efforts should be directed at moving toward sustainable practices. Unfortunately, with few financial incentives, a heavy burden is placed on government agencies to enact policy and implement regulations that will require the industry to change current wasteful practices.
The benefits from deconstruction are significant. Deconstruction offers historical, social, economic, and environmental benefits. Older buildings often contain craftsmanship, which have significant historical value to collectors. Deconstruction can carefully salvage these important historical architectural features because materials are preserved during removal. Deconstruction is more time consuming and requires more skill than simply demolishing a structure. Although the extra time required could act as a detriment, the additional jobs that can be created benefit the community. Deconstruction provides a market for labor and sales of salvaged material (Catalli and Goode, 1997). More importantly, deconstruction puts back into circulation items which may be directly used in other building applications, reducing the amount of waste sent to landfills. Currently there are few incentives to break the historical practice of landfilling debris. The occasionally higher cost of selected demolition can be offset by the increased income from salvaged materials, decreased disposal costs, and decreased costs from avoided time and expense needed to bring heavy equipment to a job site.
Deconstruction produces a flow of good quality, low-cost building materials into a community. Deconstruction also provides opportunities for the creation of value-added products made from salvaged building materials. The implementation of deconstruction results in new economic development since several businesses are needed to support a deconstruction infrastructure. Used building material associations (explained in the Deconstruction Materials section) provide outlets for salvaged reusable materials. Jobs are created for deconstruction businesses. Business growth is experienced by demolition contractors since those who regularly demolish usually practice some form of deconstruction such as cherry picking. In addition to used building material stores, value added manufacturing, and the preservation of landfill space, deconstruction develops a long term, economically viable sector of the construction industry for waste reduction, resource conservation, and job creation.
One example of the benefits of deconstruction is removing sound materials from the waste stream, eliminating the need to harvest and mill new lumber and manufacture new household basics. Even when building codes prevent the use of old, ungraded boards directly in a new home, they can be used in concrete forms, walkways, and equipment sheds at the construction site. Deconstruction also provides low income and thrifty people with cheap building materials and potential tax incentives.
5.1 Social Benefits
The basic skills needed for deconstruction can be easily learned and transferred to the construction trades. Unskilled and low-skilled workers can receive on-the-job training in use of basic tools and techniques for carpentry, construction, and materials recovery. Training individuals can also foster community oriented enterprises such as deconstruction service companies, used building materials stores, and small manufacturing centers while protecting the community’s environmental health.
A review of deconstruction case studies shows deconstruction requires significantly more labor than traditional demolition methods. As a result of the labor intensity, deconstruction provides a significant amount of employment opportunities. In 1997, The Center for Economic Conversion estimated that there are ten resource recovery jobs for every one landfill job. Deconstruction can supply useful materials to building material yards, recycling centers, and re-manufacturing enterprises that create additional jobs and revenue within a community.
|Case Study: Public Housing
Location: Hartford, Ct
Since 1993, the US Department of Housing and Urban Development’s (HUD) HOPE VI program has disbursed approximately $500 million per year to local housing authorities for demolition, construction, or rehabilitation of public housing, as well as for planning and technical assistance. In FY 1998, the Hope VI budget included $550 million, of which $26 million was allocated for demolition and for revitalization of public housing designed to meet the special need and physical requirements of the elderly. A secondary goal of HOPE VI is to move public housing residents from the welfare rolls to living-wage employment. In addition, HUD’s Section 3 requirements promote job creation and business development for public housing residents.
Recognizing that deconstruction provides communities with a unique opportunity to combine removal of structures with job training/employment, the Hartford Housing Authority (HHA) is the first housing authority in the nation to require a deconstruction program as part of its HOPE VI program. In 1998 HUD agreed to allow recipients of HOPE VI grants to re-invest demolition funds for deconstruction projects. If deconstruction were employed in conjunction with demolition to remove public housing across the country, as well as other public and private sector structures, communities could reap substantial environmental, economic and social benefits for their residents.
Cities can look to deconstruction as a way to address their abandoned housing problems while creating job training. The city of Hartford, CT. has set aside funding from the State to deconstruct 350 abandoned buildings as part of a program to develop deconstruction service companies that train workers for skilled employment.
5.2 Economic Benefits
Economic benefits can result from the sale of salvaged materials. There are markets and demands for materials that may only be attained from salvage operations. Regions of California have experienced favorable revenues and business growth from deconstruction operations.
|Case Study: Reclaimed Lumber Sales / Business Revenue
Location: Berkeley, California
EcoTimber of Berkeley expects revenues from its reclaimed timber sales to climb from about $100,000 last year to $500,000 this year. The company started in 1992 importing hardwood from certified well-managed forests. Because that market was small they branched into selling salvaged timber in their product lines. This year reclaimed timber will account for about 15% of the company’s anticipated $4 million revenue. EcoTimber is now remilling and marketing more than 2 million board feet of timber including old-growth redwoods and Douglas fir.
|Case Study: Material Revenue
Reclaimed wood from deconstructed military warehouses such as hand hewn barn beams sell for as much as $15 per linear foot. Old oak flooring goes for $6 a square foot, compared to $3.50 for new oak.
Traditional demolition contractors can expand their business to include deconstruction. By expanding their businesses increased revenues may be realized. The sale of salvaged materials will increase salvaged material company revenue while providing low cost building materials to the public. Although mentioned before but difficult to quantify are the social benefits resulting from creating jobs and training opportunities for low-skilled workers. These community and personal benefits are invaluable.
|Case Study: Create Business
The Green Institute of Minneapolis launched its DeConstruction Services in 1997 to improve the quality and quantity of inventory at the ReUse Center, its 26,000 square foot store that since 1995 has offered salvaged, reusable building materials. Now DeConstruction Services has four crews trained and insured to salvage reusable materials from buildings scheduled for demolition. About 60 percent of the salvaged materials sell at the deconstruction work sites or from the program’s warehouse. The ReUse Center and DeConstruction Services expect more than $800,000 in sales this year.
5.3 Environmental Benefits
Since construction and demolition sites are one of the largest sources – over 20% in the State of Florida – of waste headed for landfills, deconstruction can help the counties and local communities reach recycling and landfill diversion goals. The Riverdale project report notes that potential environmental benefits of deconstruction are not reflected in the direct cost comparisons. Direct cost comparisons between demolition and deconstruction are often misleading since environmental benefits can be difficult to quantify. Environmental benefits such as decreasing site disturbance, conserving landfill space, saving energy by reusing materials, and decreasing air-borne lead, asbestos and nuisance dust at and around the job site (NAHB, 1997). It is often difficult to quantify the environmental, personal, worker and neighborhood benefits of reducing job site pollution. When many individuals or businesses evaluate deconstruction environmental factors are often not taken into consideration. Often benefits to the environment can far outweigh any costs to the industry or business. Although difficult to quantify, environmental considerations must play a major role in the full cost accounting of structures. Every day companies place price tags on the environment, for example the money paid out to Alaska by Exxon or fines collected by the EPA. These monies often are paid after the damage has occurred. By implementing deconstruction, large amounts of usable materials can be recovered and diverted from landfills. This environmentally sound process closes the loop in the construction material cycle, keeping construction materials in circulation as long as possible.
5.3.1 Recovery Rates
The following recovery rate listed in Table 9 are from different case studies. These rates show how much of an affect deconstruction can have on the waste stream. The recovery rates range from 50 – 90 percent.
Although at first glance these numbers seem high this is the total amount of waste diverted from the landfill. The numbers do not necessarily represent the percentage of materials that were deconstructed and specifically reused. The percentages represent the total diversion rate through reuse and recycling. These numbers include recycled materials such as a concrete slab crushed and used as road base or the glass from windowpanes sent to a recycling facility.
These recovery rates are significant because they show the potential for reduction in this significant portion of the waste stream. As stated in Chapter 4 approximately 125 million tons of waste in the US is attributed to demolition and renovation debris. Deconstruction provides the potential to reduce this waste stream by 62 – 113 million tons per year. In addition to this huge potential environmental savings there are the potential monetary savings. As demonstrated in Chapter 4 Figure 3, tipping fees for the country are following an increasing trend. This trend is due to many factors such as increased environmental awareness and increasing regulations. This increase in tipping fees is also not isolated the US. In British Columbia, landfill tipping fees have doubled since 1989 and continue to rise. Contractors are required to submit a waste plan and two bid prices, one for demolition and one for deconstruction.
Case Study: Recovery Rates
A deconstruction pilot project was conducted on one building at the Oakalla prison complex, which was slated for demolition. The 12,000 sq. ft. building constructed in the 1960’s consisted of 64% wood and 30% concrete. The project reused 97% of the wood and diverted all of the concrete from landfill. A major problem was time. Demolition could have been done in a few days, deconstruction took a number of weeks. The additional labor costs were found to be justified by the value of the wood. With conventional demolition, 92% of the material would have gone to the landfill. Deconstruction reduced this amount to only 5%.
A four week project to deconstruct a four-story house, a barn and a garage in Canada provided employment while diverting a significant percentage of material from the waste stream. In this instance, By dEsign Consultants conducted a waste audit at the outset of the project to quantify the volume and weight of all materials that would be generated. This was used as a planning tool throughout the project, for example, to anticipate sorting and storage needs.
Case Study: House/barn/garage
The deconstruction of a four-story house, a barn, and a garage in Canada provided employment while diverting 91% of the potential waste from the landfill. By dEsign Consultants of Ontario experienced a net cost of $2,000 over the demolition alternative however the project provided over $24,000 in employment to a six-person crew. (Catalli, 1997) Concrete made up the largest portion of waste but had the smallest resale value, whereas windows and finishes made up small percentages and generated relatively large revenues.
Countries in Europe also experience high percentages of construction and demolition waste. For example in Baden, Germany, the C&D waste is over 2 million tons per year and in Alsace, France over 1 million tons per year. Both regions feel it is important to recycle as much construction waste as possible, not only because of limited dumping capacities but also in order to try to preserve natural resources. Since deconstruction avoids mixing debris, there is a higher recovery rate.
Case Study: Recovery comparison
Pilot deconstruction projects
Half of each structure was deconstructed and half was demolished using traditional methods. As would be expected the study showed a higher percentage of reusable materials resulted from deconstruction. However, analyses of the costs confirm the importance of local legislation, recycling prices, and disposal prices. The Dobel project – an area with stricter disposal regulation – showed selective deconstruction was more profitable than conventional demolition. In Mulhouse, where disposal regulations are more lenient, deconstruction was twice as expensive as traditional demolition.
A third project on Strasbourg (Alsace) resulted in only 2% of the building mass being sent to the landfill. This project showed that supplemental costs caused by selective dismantling can be compensated by gains realized through the selling of reusable materials and the reduction in waste disposal expenses. For the third project, conventional demolition would have cost 2.4 times more than deconstructing.
In Canada the combined implementation of deconstruction, salvage, landfill diversion and resale have resulted in large diversion rates.
|Case Study: Diversion of Waste
It is estimated that last year over 100 million tons of material was diverted from landfill to resale. Traditional salvage yards are receiving “face-lifts” to appeal to a new market segment. For example, goods are arranged similar to those found in building supply shops, organized by size and material type.
5.3.2 Landfill Preservation
One of the key environmental benefits of deconstruction is the preservation of landfill space. Deconstruction reduces the waste stream and extends the landfills potential service lives. Materials are separated at the source during deconstruction allowing materials that cannot be used immediately to be recycled.
|Case Study: Landfill Preservation
Location: De Moines
Facing dwindling capacity, Landfill of Des Moines has extended the life of its construction and demolition debris landfill by recycling an extensive list of materials. A grant from the Iowa Department of Natural Resources helped the company – now Central Construction and Demolition Recycling, Inc. – shift its business toward recycling. With five of its 23 acres dedicated to recycling, Central recycled 43% of the 87,038 tons of material it received last year.
5.3.3 Hazardous Materials
Deconstruction, by its nature, forces the proper removal and handling of hazardous materials before the remainder of the building’s parts can be salvaged. Due to the hands on, non-mechanical nature of deconstruction human exposure to potentially hazardous materials is elevated. With traditional demolition, worker exposure is limited – structures often are not thoroughly examined for potential hazards since most workers do not deal directly (hands on) with the structures components. Often potentially hazardous materials end up in the landfill simply because they were undetected prior to demolition. Due to the thorough examination and exploration of structures during the deconstruction process, hazardous materials are identified and disposed of properly.
Deconstruction has social, economic and environmental benefits. Deconstruction can assist in the rebuilding of dilapidated neighborhoods, provide employment for relatively unskilled workers, provide low cost building materials and greatly reduce the amount of waste sent to landfills. As a result, landfill space is preserved ultimately saving the local governments the costs associated with closing existing landfills. In reality there are many valuable building materials that can be and are salvaged from buildings slated for demolition. Deconstruction provides an environmentally friendly alternative to recapture the value of these materials for reuse.
Implementing deconstruction is not a simple task. SuPCCEssful implementation cannot occur without a support structure of government, regulations, and businesses working together toward a joint goal. Deconstruction can result in environmentally sound community economic development. Many environmental benefits can be realized through the formation of partnerships between environmental organizations, government agencies, and the private sector. It is necessary to first educate and train those who are potential deconstructors. Individuals working in the field of demolition are primary targets. In addition to education and training, outlets for the salvaged materials must be created.
6.2 SuPCCEssful Implementations
Without legal incentives businesses will continue to operate in the least costly manner regardless of the environmental costs associated with these practices. In order to combat these practices the Dutch Government passed a law in January 1996, which states: “dumping of reusable building waste is prohibited”. As in the United States, the largest single waste stream in the Netherlands is construction and demolition waste. Construction, renovation and demolition operations in the Netherlands currently produce approximately 14 million tons of C&D waste per year. Approximately 72.36% of this waste is a result of demolition activities. Prevention and reuse are unlikely to grow if purely left up to the market forces. The Government in the Netherlands aims to direct the construction and demolition waste markets through legislation and other forms of regulations. The primary role of government is to set the constraints and establish related policies.
|Case Study: Government Policy
In April 1997, the Construction and Demolition Waste Landfill Ban was enacted. This ban prohibits the landfilling of reusable or burnable construction and demolition waste. The Landfill Ban was an important instrument to promote waste reuse and therefore increase the reuse rate. In addition to the landfill ban, the Implementation Plan for Demolition and Construction Wastes sets objectives that reuse should reach approximately 90% and that in the year 2000 no more than 10% of construction and demolition waste should be landfilled or incinerated. This Plan provides incentive to promote the separation of Construction and Demolition waste into component streams that are transported to processing plants rather than going outside the construction industry cycle. The landfill ban applies not only to reusable construction and demolition waste, but also to the residues from processing C&D waste.
In the Netherlands, waste disposal is primarily organized at the provincial levels. The Government of the Netherlands acts in a similar manner to the US government. The Federal government sets standards and the state and local governments must meet a minimum of this standard. In the Netherlands the Provinces can include regulations in their Provincial Environmental Ordinances to implement their Provincial Environmental Policy Plans. The Provinces can establish environmental policies that are stricter than the general environmental policies of the Central government. Similarly, in the US, state regulations are often more stringent than the federal regulations.
In England, approximately one sixth of the total waste is a result of construction and demolition as stated in Rethinking Construction, a report produced by Sir John Egan’s Construction Task Force 17 for the Deputy Prime Minister. This report aims at increasing efficiency through more sustainable business practices. The Task Force recommendations will enable the construction industry to work toward improving performance and sustainability. The Government is also working closely with representatives within the industry to develop a strategy for achieving more sustainable construction. A Sustainable Construction Action Group will report to the Government Construction Clients’ Panel on how Government can show the way in adopting better principles of sustainability in its procurement and operation of buildings and other built assets.
The Construction Best Practice Program will help promote the strategies of waste reduction, use of recycled materials, and whole life costing. Industry plans to establish a Sustainable Construction Industry Focus Group to encourage the necessary market transformation within the construction industry.
|Case Study: Government Agencies and Regulations
Government policy on the use of construction and demolition waste as aggregate in England is currently set out in Minerals Planning Guidance Note 6, published in April 1994. Aggregates and products made from aggregates should be recycled wherever possible and where technically, economically and environmentally aPCCEptable, construction and demolition wastes should be used instead of primary materials.
The waste, demolition, and aggregate industries have responded positively to the policy of encouraging the use of recycled materials. The structure of the recycling industry is expanding and changing rapidly, spurred on by the tighter waste regulation and the landfill tax. This enthusiasm is being captured in developing the industry strategy for more sustainable construction.
In Ontario, over 20% of waste currently heading to landfills is a result of the construction and demolition industry. The Ontario government recently passed Bill 102, a section of the “3 R’s Regulations” made under the Environmental Protection Act. The Bill puts increasing pressure on the construction industry to divert materials from the landfills. Ontario has established a target to decrease the amount of waste by at least 50% by the year 2000.
6.2.2 United States
There are several areas in the United States where deconstruction has been implemented. As seen throughout this document there are case studies spanning the nation from the east to west. However, the majority of these deconstruction projects received grant moneys to perform studies for research. This factor makes accurate calculations difficult regarding the suPCCEss of actual implementation. Full-scale suPCCEssful implementations of deconstruction are concentrated on the west coast from the San Francisco area north to the Pacific Northwest. Other cities scattered throughout the nation are achieving local suPCCEss with deconstruction. By far the region proving to be most suPCCEssful is the west coast. This region has turned deconstruction into a highly profitable alternative.
6.3 Influence Factors
Although the optimal solution for the environment is to salvage all materials, this is not the optimal economic solution for most starting deconstructors. The optimal economic solution results from many factors. Each of these factors changes based on location, building type, and regional markets. The overall economic situation plays a key role in implementation. The economics of the region, economics of the people in the region and the economics of businesses are all contributing factors. Following money, the influences most often heard by business are regulations, mandates, laws, and incentives. Without a legal or an economic push to reduce, reuse and recycle the effort is often ignored. The construction industry – comprised mostly of midsize construction firms, operates under a tight profit margin (usually around 5%). As in most industries, the construction and demolition companies are not willing to jeopardize this profit margin by implementing reuse programs or expanding their demolition practices to deconstruct if the company will not realize an immediate and significant profit. Most businesses feel it is simply not worth the financial risk of often negative monetary payoff to be environmentally friendly.
6.3.1 Regional Influences
22.214.171.124 Florida Development
Florida has one of the nation’s fastest rates of growth. Florida has been recognized nationally for the last twenty-five years as a leader in planning for growth and protecting the environment. Florida is currently the fourth most populated State and expected to become the third most populated by the year 2020 (LaFrenier, 1995). Sunny skies, pristine beaches and a balmy climate have attracted millions to vacation and live in this paradise called Florida. Aside from these natural attractions over the last century, Florida has done everything in its power to accommodate and encourage growth. The State has funded the drainage of millions of acres of wetlands and has given land grants for railroad construction, opening up vast expanses of wilderness for development. Florida continues to lure new residents by providing homestead exemptions, low property taxes and no personal income tax.
In looking at the Florida population, there are two distinctive regimes of growth. The rate of growth for the State changed significantly in the mid 1950’s (note the two distinctive line slopes) (Figure 5). Florida Population 1900 through present shows these two growth rates, one for pre – 1955 and a second for post 1955. The growth rate in the 1930’s and 1940’s was between 2.6 and 3.7 percent. The growth rate for Florida in the 1950’s was approximately 6 percent.
Florida’s rising population naturally results in increased demands for public services. As an example, each year the State needs an additional 800 miles of new roads, constructs 730 new classrooms, and hires 740 more police officers (LaFrenie, 1995). Also required are additional water and sewer systems, prisons, courts, fire and emergency rescue, and other governmental services. This growth has costs, especially to the natural environment. For example, every day 450 acres of forest and 410 acres of farmland are cleared in the State. Each year the State needs an additional 40.5 million gallons of fresh water, generates 36 million gallons of wastewater, and produces an additional 12.8 million pounds of garbage (LaFrenier, 1995).
Over the last 50 years, people have moved from the cities to suburbs. The shift from denser to more sprawling communities has resulted in increasing dependency on automobiles and the need to increase the network of expressways. Because the suburbs are less compact than cities, it costs more on a per capita basis to provide public services (Florida Planning, 1998). The sprawling development requires more roads, longer sewer lines and other infrastructure to serve it.
Adequate public services and infrastructure are essential to maintaining Florida’s economy and our quality of life. As our communities grow, the demand for public services and facilities increases. There are two types of costs associated with providing public services. First, there are up front – or capital – costs to build and install public facilities. Then there are the costs associated with their operation, maintenance and repair. Effective growth management can help control the cost of paying for public services and infrastructure by managing the location, pattern and timing of growth.
As development spreads out from existing urban areas, especially at low residential densities, the cost of providing and maintaining public services increases. Roads and sewer lines have to be extended, and often, new school, fire stations, and libraries are required. Meanwhile, existing public facilities in the urbanized areas may still have unused capacity (Florida Planning, 1998).
Numerous studies have shown that it costs government more to provide public services and infrastructure to sprawling, low density subdivisions than to existing urbanized areas. For example, it has been demonstrated that for new residential development ranging in density from one unit per five acres to four and a half units per acre, the ongoing public costs exceed the revenues. Research has also concluded that public cost of providing central sewer, water, streets and school to low density development just ten miles away from existing sewer and water facilities and employment centers is dramatically higher than the costs associated with serving higher density residential areas near existing infrastructure.
One example compared sprawl to compact growth, assuming the same number of people and the same number of jobs. The results were that compact growth, which has a mix of housing types at higher densities, consumed 45 percent less land, and cost 25 percent less for roads, 15 percent less for utilities, 5 percent less for housing, and 2 percent less for other public costs than sprawling development at less than three units per acre (LaFrenier, 1995).
|Case Study: Sprawl
Location: South Florida
In a study completed by Dr. Robert W. Burchell, called Eastward Ho! Development Futures: Paths to More Efficient Growth in Southeast Florida analyzed the costs of this rapidly growing region. The cost of accommodating projected regional growth of 2.4 million people in a region that currently has 5 million residents were estimated. (REF) The cost is projected to be more than $10.5 billion over the next 20 years if current “sprawl” development patterns continue into the future. The report suggests that the region has an opportunity to realize a cost savings of nearly $6.15 billion through infill development (Infill development including renovation of existing structures could be a direct source of materials for the deconstruction industry). Infill could result in the preservation of 67,725 total acres of developable land; 52,856 acres of prime farmland and 13,887 acres of fragile environmental lands. Savings of an additional $157 million in waste capital costs, $135.6 million in sewer capital costs, and $1.54 billion in local road costs could also result from in fill.
Encouraging revitalization and redevelopment of older communities can provide significant savings for local and regional governments while providing an environment conducive to the implementation of deconstruction. Deconstruction significantly adds to the environmental benefits of revitalization and infill.
In addition to the great infill potential that several coastal cities provide, Florida’s main industry, tourism may also provide potential environmental benefit. Florida tourists, approximately 43 million people in 1996, contributed $35.31 billion in related sales to the State economy. While tourism used to rely heavily on sunshine and beaches, in recent years more visitors are seeking out natural, historical, and cultural resources. Known as “ecotourism” and “heritage tourism”, these newly-recognized facets of the industry offer great economic potential (Sustainable Future, 1998). Ecotourism is growing at a rate of 30 percent per year (#10). With Florida’s number one source on income being tourism and the rapidly increasing trend of ecotourism, it is in the States best interest to preserve the natural environment to support this industry.
126.96.36.199 National Availability of Buildings
In looking at the demolition and deconstruction industry it is important to identify the feedstock for this industry. Nationally, regionally, and locally building types vary drastically. The building stock also varies based on classification – i.e. industrial, residential, or commercial. Availability of buildings is not the issue so to speak; it is the availability of buildings worth being deconstructed. Currently it is necessary to be extremely choosy in the selection of a building for deconstruction. Contractors still rely in their old cherry picking rule of thumb to deconstruct only those buildings that appear to have historically high-ticket item materials.
188.8.131.52.1 Public Housing
Across the nation, an estimated 200,000 public housing units will be demolished as a result of HOPE VI. For example, the City of Chicago plans to demolish 11,000 apartments, nearly 40 percent of its public housing stock for families, over the next 15 years.
184.108.40.206.2 US Military Bases
Hundreds of military bases across the country are being closed or realigned and converted to civilian uses. Redeveloping these properties often requires buildings to be removed because they are obsolete or inconsistent with reuse plans. Many structures on military bases do not meet standard building codes and must therefore be removed or rehabilitated to protect public safety. Deconstruction, which has already begun on some military bases, can help the military reach a 40% solid waste reduction goal. The 40% goal was scheduled to be introduced by the Department of Defense in 1999. The military is encouraging deconstruction, salvage, and reuse.
Recent military base deconstruction efforts demonstrate real world improvement in economic efficiency. Contractor bids to demolish and landfill the Presidio and Port of Oakland buildings came in substantially lower than salvage bids, however, when the profits from sales of materials is added, the numbers favor salvaging. Estimated costs for demolishing, $150,000; estimated cost for deconstructing, $330,000; however, the income from lumber sales, $280,000 resulted in a net cost of only $50,000 if the buildings were deconstructed.
|Case Study: Presidio – Military Reservation
Location: San Francisco
On the Presidio project the government required as many materials as possible from the project be salvaged, reused or recycled in order to minimize the impact of construction waste in landfills and to minimize the expenditure of energy and cost – benefit analysis for recycling. Buildings were offered intact for removal and reuse but there were no takers.
Two buildings were ultimately deconstructed, one by the consortium and one by a general contractor. The deconstruction by the general contractor was not documented, however the deconstruction by the consortium took six weeks and provided full time jobs. Over 90% of the wood in the building was recovered for reuse. Most of the costs were for labor. Workers were paid a total of $33,000, equipment and administrative costs brought the total project cost to $55,000. Revenues from the sale of lumber were estimated at $43,000. The project also received a donation from the National Science Foundation and a credit for avoided demolition costs that enabled it to turn a small profit. Case Study: Project Problem
Location: Presidio – San Francisco
A problem that exists during deconstruction is the potential for devaluation of recovered materials due to environmental damage, difficulty of dealing with personal injury liability and handling of hazardous materials.
Two tiered market for recovered materials:
- high-end market for architectural salvage and large-dimension beams sold to affluent buyers looking for fashionably aged building components.
- low-end market of obsolete plumbing fixtures, recycled paint and other items not in good condition, which were sold very cheaply by salvagers
The Building #733 project in Oakland showed the benefits of combining deconstructable building stock, at risk youth and an experienced personnel.
|Case Study: Building D-733
Location: Oakland (across the San Francisco Bay)
The Youth Employment Partnership (YEP), a job training organization for high risk, low income youth worked with Beyond Waste Inc. to deconstruct Building D-733 at the US. Navy’s format Fleet Industrial Supply Center. Four supervisors and fifteen youths (who were paid $6.50 to $9.00 per hour) diverted over 425 tons of material from the local landfill and salvaged 315,000 board feet of lumber. The projects overall recovery rate was 70 percent, not including the 110 tons of wood that was chipped for mulch and fuel.
220.127.116.11.3 Florida Building Stock
The majority of Florida structures are not built of old growth timbers and if so they are some of the few historic structures. Although Florida has few historic structures, there are a large quantity of smaller dimensional lumber that could be salvaged. In addition to the dimensional lumber, a common building material is CMU or the concrete masonry unit. These units could be salvaged and used as road base or aggregate to support the growing need for road expansion in the State. The bottom line with deconstruction is that each structure must be examined individually to determine what materials that structure will produce.
The population trends for Florida help to determine what the influx of new residents may be and how the past influxes have affected the State. In looking at the Florida building stock – the majority of the States growth occurred in the 1950’s. According to Pete Hendricks, a veteran deconstructor, buildings built before WWII provide excellent building stock for deconstruction. However we note that the growth spurt for the State of Florida occurred after WWII. There is a mix of construction styles and categories throughout the State. Wood frame and concrete structures dominate the State. Although it may not appear that the State is ideal for salvaging and resale of materials, these are not the only benefits resulting from deconstruction. The State should focus on the environment through lessening virgin land development, conservation of resources, and extending the service lives of landfills.
18.104.22.168 Tipping Fees
As discussed previously, there is a relationship between regional tipping fees and the effort seen in the industry to find alternative waste disposal methods. As tipping fees rise, the cost of doing business related to demolition, renovation, and new construction also rises. Inflation and markets also affect tipping fee prices.
While higher tipping fees create more incentives for earth friendly waste disposal alternatives, they are not the only driving factor. There are many areas throughout the nation that experience high tipping fees that show no signs of implementing deconstruction or mandating reuse or recycling. In these regions the tipping fees are simply considered the cost of doing business. As landfills close and tipping fees rise the construction industry passes the increased expense of waste disposal to the owner of the construction project who in turn passes the extra expense along to society in the form of rent or the new purchase price. Society needs to decide where the money should be spent, either in preserving the environment now or footing a higher bill later.
6.3.2 Feasibility and Market
Determining the feasibility and market for deconstruction plays a key role in the suPCCEss of this effort. A network of businesses must be created to allow for the smooth flow of goods. The product flow of deconstructed materials mimics the traditional flow of materials. Traditionally, materials follow resource extraction, to manufacturing, to marketing and distribution. Deconstructed materials must follow a similar pattern, however in this case, the definition of the stages of flow change. Traditional resource extraction, what we think of as mining, for example, is now changed to physically removing materials – deconstructing – to acquire the valuable resources. When thinking of manufacturing, traditionally, we think of changing that raw material into a desirable product. The new definition of manufacturing in this case is taking the salvaged items and performing repairs, recertification, or adaptation to what society needs. Marketing at this stage is similar to that for new products. A clientele must be established to facilitate the flow of these products back into circulation. Marketing requires not only a supply of these products, but also a need, if not demand, for these deconstructed materials.
|Case Study: Demand for Deconstructed Materials
Apart from the policy of the Dutch government, there is demand from the road building industry, which needs the secondary materials such as asphalt, concrete, and mixed granulate for their construction. Concrete and mixed granulates prove to be a good alternative for the construction of road base and asphalt can be reused in new asphalt.
Builders must make tradeoffs when it comes to reusing “older” materials. Use of salvaged materials is both beneficial and potentially detrimental. On the positive side, for example, salvagers may have the option of deconstructing an old factory floor, which is made of solid old growth wood. This product is not only in demand, but valuable and difficult to find in today’s market. On the other end of the spectrum, old plumbing fixtures, such as toilets, may be salvaged. When considering their reuse, it is important to consider the tradeoff such as not selecting a newer low flush toilet. Which environmental benefit is better, salvaging a toilet from potentially entering a landfill or conserving the water needed to operate the device. In looking at these choices – saving landfill space or saving water – returns us to what is the primary concern of society. How will society choose to allocate its limited resources – how many years of potable water remain – what technological advances may be made that may change societies conservation focus.
22.214.171.124 Florida Versus San Francisco
The current market climate in the greater San Francisco Bay Area is perfect for the expansion of existing reclaimed lumber markets and the creation of new ones. The economic downturn that stalled housing that started several years ago has lifted, creating a steady growth rate in the building industry. In addition, the metropolitan areas that make up this region have very promising mix of positive indicators. The Bay area ranks high above the national average in disposable income, average education level, average per capita income and has a very high percentage of people in the age bracket between 20 and 60, the ages when people build houses. In addition, the level of environmental awareness and demonstrated financial commitment to environmental change is high.
San Francisco has an extensive network of business established to support a suPCCEssful deconstruction infrastructure. For example, the Wood Reuse Working Group was formed in 1996 to assist non-profit organizations and their for profit partners in the development of value added markets for wood reclaimed through deconstruction of wooden structures.
In general, Florida does not mimic the existing environment of San Francisco. Florida on average has a lower level of disposable income, lower educational level, lower per capita income, general environmental awareness is lower, and the State has a significantly higher percentage of retirees. Although it is not accurate to compare the State as a whole to one specific region or city on the west coast, for the most part the regional behavior of Florida is uniform.
Some regions in the State show conditions very similar to that of San Francisco. For example, three South Florida coastal metro areas rank in the top 20 nationally in per capita income. The West Palm Beach – Boca Raton metropolitan area, rank the highest in Florida and third in the nation behind San Francisco and the Connecticut metropolitan area. The Naples area ranks seventh nationally and the Sarasota-Bradenton area is 16th. With similar incomes, these regions also experiences high growth rates and have a higher density than non-coastal regions of the State. However, the disadvantage Florida exhibits is the lack of older buildings.
6.4 Environmental Policy and Incentives
There are very few policies in place on a national level that mandate environmentally friendly construction, buildings, designs, and materials. Without policy favoring sustainability, researchers look to the governments to offer incentives that will begin to sway the construction industry minds when designing and building for the future. Currently there are few incentives, and those that are offered, are not nearly enough to persuade big business to invest the extra money in designing for the environment. The US Environmental Protection Agency (EPA) runs a program that started in 1992 called Design for the Environment. This program forms voluntary partnerships with industry, universities, research institutions, public interest groups, and other government agencies. The program attempts to change current business practices and to reach people and industries that have the power to make major design and engineering changes. Their ultimate goal is to incorporate environmental considerations into the traditional business decision-making process.
The US Department of Energy, Office of Pollution Prevention, has begun a Pollution Prevention by Design project in an attempt to help engineers, designers, and planners incorporate pollution prevention strategies into the design of new products, processes, and facilities. The problem facing the industry is not the invention, or innovation, but the education and implementation of new techniques and concepts.
Existing Federal Laws and Executive Orders, which pertain to the construction industry, are primarily focused on energy conservation. The following is a listing of these regulations in place (Sustainable Systems, 1994):
- Energy Policy and Conservation Act (EPCA of 1975)
- Resource Conservation and Recovery Act (RCRA of 1976)
- National Energy Conservation Policy Act (NECPA of 1978)
- Comprehensive Omnibus Budget Reconciliation Act (COBRA of 1985)
- Federal Energy Management Improvement Act (FEMIA of 1988)
- Energy Policy Act (EPACT of 1992)
- Executive Memorandum (“Environmentally and Economically Beneficial Practices on Federal Landscaped Grounds”)
- Executive Orders: 12759, 12843, 12844, 12845, 12856, 12873, 12902
Over the past two decades, public concern and support for the environmental protection have risen significantly spurring the development of an expansive array of new policies that substantially increased the government’s responsibilities for the environment and natural resources (Kraft, 1997). The implementation of these policies, however, has been far more difficult and controversial. Government is an important player in the environmental arena, but it cannot pursue forceful initiatives unless the public supports such action. Ultimately, society’s values will fuel the government’s response to a rapidly changing world environment that will involve severe economic and social dislocations in the future. Environmental policy is difficult to predict, the US is moving from a nation that exploited resources without concern for the future to one that must shift to sustainability if it is to maintain the quality of life for present and future generations. If green plans were proposed in the US, they would survive the political process (Johnson, 1996). Several States have already implemented their own progressive environmental policies that are stricter than Federal regulations.
Two major changes in federal policy are also creating major opportunities for deconstruction: the demolition of public housing under the HOPE VI programs and the conversion of closed military bases across the US If deconstruction were employed in conjunction with demolition to remove public housing across the country, as well as other public and private sector structures, communities could reach substantial environmental, economic, and social benefits for their residents, at little or no additional cost compared to traditional demolition.
Forty-four states and the District of Columbia have set solid waste diversion and/or recycling goals (Glenn, 1998). Several states are beginning to insist on environmental preservation. Blatant disregard for the environment is no longer tolerated. An example of progressive environmental association is the California Resource Recovery Association. This organization is actively pursuing manufacturer responsibility legislation. The principles the association wishes to incorporate into the legislation follow:
|The California Resource Recovery Association|
If it can’t be assimilated into the environment, then it can only be leased Anything not biodegradable/recyclable is tagged with its constituents and manufacturer Mandated deposit laws for certain materials Mandatory separation of wastes Mandatory procurement of recycling products for public projects Product disposal borne at manufacturer level, “advanced disposal fees” for manufacturer wastes Advanced fees mean that disposal is calculated upfront as part of the costs of producing the product and is internalized by company. This is like pollution permits, whereby quotas could be traded between those with product stewardship and those without, this would be called a “processing fee” Eco-labeling and materials labeling is consistent. Product made with minimum recycled content requirements.
Government and the public tend to associate incentives with money. Although this is often the standard incentive it is not the only way to provide incentives. Incentives may be disguised as disincentives or penalties for disposal. By creating an environment not conducive to wasteful practices an incentive is created to waste less. On a local level, the state could mandate all demolition companies attend deconstruction seminars. Attendance could also be required prior to the issuing of a demolition permit. Contractors are required to attend continuing education courses to maintain their licenses. A course in deconstruction could be required. A disincentive can also be to raise the cost of demolition permits while issuing deconstruction permits at no cost. There are many options for local and regional governments to explore. It is important to implement alternatives that are specific to the region and local economy.
Although Florida is known for attracting growth, over the last twenty-five years the State has also became nationally recognized for its efforts to manage growth and protect the environment. In the early 1970’s foresighted leaders began to recognize that rapid population increase, the resulting damaging impacts on the environment, and the declining investment in public infrastructure could lead to a diminished quality of life. The Florida Legislature took decisive and progressive action to adopt laws intended to protect the environment and manage growth.
126.96.36.199 Solid Waste Management Plan
The Solid Waste Management Plan, completed in 1985, looked at future needs for landfills and possible recycling.
188.8.131.52 Growth Management Act
The Growth Management Act establishes a pyramid of planning with State oversight and minimum planning standards. At the top of the pyramid is the State Comprehensive Plan with broad goals and policies dealing with a range of subjects from education to the environment. Eleven regional planning councils are required to adopt Strategic Regional Policy Plans consistent with the State plan, to address regional issues. Then there are approximately 470 local government comprehensive plans, which are supposed to be consistent with the regional and State plans.
State legislation passed in 1993 recognized that the Regional Planning Council (RPC) is Florida’s only multipurpose regional entity that is in a position to plan coordinated intergovernmental solution to growth-related problems on greater than local issues. Figure 6 below shows the State broken into the eleven regional planning councils. In assisting the RPC to perform their roles, the legislation requires each RPC to develop a Strategic Regional Policy Plan (SRPP) to replace the current Comprehensive Regional Policy Plan.
The regions were directed, among other items, to achieve long term efficient and sustainable development patterns by guiding development and redevelopment … where negative impacts on the natural environment will be least significant…. In addition direction is also given to revitalize deteriorating urban areas, … promote neighborhood revitalization, …protect and manage natural resources of regional significance and manage growth and development to ensure the sustainability of the Regions through policies …”
Deconstruction specifically targets several of the issues the Regional Planning councils were directed to address. Specifically issues such as revitalizing deteriorating areas and promoting neighborhood revitalization are benefits of deconstruction. Deconstruction also reduces the State dependency on natural resources. By establishing deconstruction, the RPC can attain their State growth goals.
The Growth Management Act of 1985 addresses waste disposal services and facility planning. This act requires that Florida counties have a funded plan to have waste disposal facilities available when needed. The comprehensive plans should:
- Guide and control future development
- Overcome present problems, and deal effectively with future problems which may result from the use and development of land
- Preserve, promote, protect, and improve the public health, safety, comfort and good order
- Protect human, environmental, social and economic resources.
The local comprehensive plans must contain several sections, called elements, which deal with specific aspects of a community’s development: capital improvements, future land use, solid waste, natural resource conservation, recreation and open space, housing, and historic preservation are a few of these elements specified. Each element contains goals, objectives and policies.
184.108.40.206 The Sustainable Communities Demonstration Project
The Florida Legislature enacted this Project in 1996 to help move Florida closer to sustainability. This project authorized the Department of Community Affairs to designate pilot communities to serve as models for sustainability (Florida Planning, Ecotourism, 1998). Five designated communities are to develop innovative public and private financial and regulatory incentives to promote six broad principles of community planning: restoring key ecosystems; achieving a cleaner, healthier environment; limiting urban sprawl; protecting wildlife and natural areas; promoting the efficient use of land; and creating quality communities and jobs. Based on these six principles, deconstruction can help to attain the goals set out by regional governments.
220.127.116.11 Solid Waste Management Act
The 1988 Resource Recovery and Solid Waste Management Act (SWMA) require that Florida counties phase in recycling. The counties must recycle or produce usable energy from 30% of their waste by 1994. The act is not clear in defining whether the mandatory 30% goal that must be achieved by each county is a waste reduction or a recycling goal. The act defines recycling as the reuse of a material that would not otherwise occur, while waste reduction refers to the effort to produce less waste materials (or things to be managed) in the first place.
The 1988 mandate of a 30 percent recycling goal was modified in 1993. The 1993 modification exempts all counties with a population under 75,000 from having to reach the goal if they provided their citizens with the opportunity to recycle. The 1988 SWMA also requires each county achieve a 50 percent recycling goal of specific materials. Materials such as newspaper, glass, plastic bottles, aluminum cans, and steel cans.
Table 10 shows the percentages of the total waste stream comprised by these five materials.
These materials combined make up only 10.7% of the total waste stream. It is much more important to target the construction and demolition waste which is over 20% of the waste stream. Government’s efforts to encourage and mandate recycling is a great step forward. However, although continually improving, currently the emphasis is not being placed on the correct materials. The original recycling mandates were initially designed to initiate residential recycling. The basis for the political decisions most likely was influenced by what materials could be easily recycled versus the materials that could significantly reduce the waste stream. Recycling is a difficult and expensive task and requires specialized equipment. Ultimately the best choice is to reduce the waste being produced. Instead of or in addition to mandatory recycling goal, mandatory reuse and reduction percentages are needed to provide a significant impact on the waste stream.
This type of mandatory recycling should be put in place for C&D materials, as they are one of the largest components of the solid waste stream. (Paper, yard trash and C&D debris made up 63% of the waste stream in 1997, 62% in 1996, and 64% in 1995.)
2000 Preservation 2000 was created by Florida Legislature as a ten year, $3 billion land and water conservation program.
6.4.3 Government Support
Within the State of Florida the DEP has taken an active role in improving and securing funds for research efforts to study, analyze and provide guidance for waste reduction. They currently have several projects underway focusing specifically on C&D waste. Several other federal government agencies demonstrated support for deconstruction by providing financial and technical assistance to pilot projects across the country. The US EPA supported the Riverdale Housing Project. The EPA provided grant funding to the National Association of Home Builders Research Center, the Green Institute, and the materials for the Future Foundation. In addition to the financial support, the EPA has also provided technical assistance on deconstruction projects. The Department of Health and Human Services’ (HHS), Office of Community Services, The Department of Defense, Office of Economic Adjustment, and the US Department of Agriculture’s Forest Products Lab (FPL) have all contributed to the deconstruction research effort. The FPL has been evaluating the grades and strength characteristics of used lumber and timber. They are working cooperatively with lumber grading agencies to develop grading criteria and grade stamps for used lumber.
|Case Study: Implementation
Location: Hartford Ct.
The City of Hartford, Connecticut, has set aside funding from a State demolition grant to deconstruct 350 abandoned buildings as part of a program to develop deconstruction service companies that train workers for skilled employment.
Other forms of support as seen in the Netherlands include the government restricting business partners to promote more environmentally friendly practices.
|Case Study: Business Certification and Government Policy
Babex, the Netherlands industry association of demolition contractors, took the initiative to set up a certification system for demolition companies by drawing up the draft National Assessment Guidelines for the KOMO2 Demolition Process Certificate. This assessment guideline includes requirements for
- The management and quality assurance of the demolition process
- The structure to be demolished and its location
- The materials recovered by demolition.
Babex has also drafted definition sheets that describe the requirements the deconstructed materials must meet for several types of reusable demolition wastes.
The assessment guidelines greatly increase the options for higher level of reuse. Separation is most effectively carried out at the source. Before starting the demolition operations the demolition contractor has to consider the materials used in the structure. The expected materials and volumes have to be described in the demolition document. This document should also identify the disposal routes for the materials. After completion of the demolition operations the actual quantities of materials is determined and the volumes reused, land filled or otherwise disposed of are recorded.
The advantage of keeping such records is that after a few years the trends in the volume and nature of the materials will become clearer. This will enable both demolition contractors and processors to anticipate these developments.
In a covenant closed with the industry the central government has declared that it will only do business with certified companies, once there are a sufficient number of demolition contractors holding process certificates. Like the waste sorting business, only certified demolition contractors would be allowed to deliver non-reusable demolition waste to landfills.
6.5 Barriers to Establishment
The use of salvaged materials can only be suPCCEssfully implemented if there are not lower cost new materials that will serve the same purpose. Currently the sale of antique or historical materials is suPCCEssful, however, the sale of salvaged windows which may not have the same energy efficiency of new windows may carry other detrimental environmental affects. The bottom line is that the salvaged materials either need to be less expensive than the new materials or have some characteristic that makes them unique to interested buyer.
As stated previously, it is necessary to have knowledge, incentives, and coordination. The main problem is the transfer of knowledge. To facilitate this transfer of knowledge, researchers must move slowly to determine the feasibility of existing alternatives. Many environmental strategies are not possible, either as a result of existing regulatory barriers, economic constraints, or lack of public aPCCEptance. Currently the greatest barriers to non-traditional construction and demolition techniques are cost and attitude. The primary concern of business is to make a profit. At the present time, in most regions, it is not cost effective to alter traditional, tired and true techniques. Another challenge is changing the industries attitude, or more to the point, grabbing the attention of industry long enough to provide them with the appropriate tools to make an educated decision about their building options.
6.5.1 Project time requirements
Project time constraints can limit options with respect to deconstruction. Often by the time the demolition contractor is contacted the project owner is under a time constraint requiring construction to begin in a matter of days. This time constraint will not allow for the deconstruction process to occur. The deconstruction process requires significantly more time than traditional demolition. Possible alternatives such as mandatory waiting periods for demolition in addition to public announcement/ advertisements and or direct contact with demolition/ deconstruction contractors to increase their awareness of the opportunity could be an invaluable incentive to increase deconstruction.
6.5.2 Salvage Material and Market Variation
Unfortunately due to the wide variety of buildings available for deconstruction there is a variety of materials produced from this disassembly. The unsure quality and quantity of this used building materials feed stock means that users cannot rely on a constant and consistent supply. For those willing to use the materials, this inconsistency provides a great disincentive.
6.5.3 Strength of market demand for used building materials
The market demand for old growth high quality large timbers will always exist, however there is very little existing demand for denailed standard 2×4’s. The cost of new materials is simply too low to drive the consumer to venture to other markets for building materials – markets such as salvaged materials. It is possible that the new material supply could be subject to a future disposal cost fee – such as in Europe where manufacturers of products are charged the disposal cost of their packaging materials. Or as in the automotive industry, the manufacturer is required to “take-back” and properly dispose of the vehicle after use. The major glitch with this effort of assigning responsibility of the initial source is the changing of hands of structures – and the rate construction companies go out of business.
6.5.4 Land Value
Land value often dictates redevelopment or new development. These efforts should be concentrated in areas where land is scarce and costly – where people are more likely to redevelop than simply develop. Emphasis can also be placed in areas where the land in relatively inexpensive – developing new land indeed results in an infrastructure burden and the unnecessary development of pristine undisturbed land.
6.5.5 Mechanical Properties of Reclaimed Materials
Although public interest in utilizing recycled wood resources is increasing, several technical constraints hinder widespread aPCCEptance. The technical obstacles hinder general aPCCEptance in the marketplace and more specifically, aPCCEptance by building officials at the jobsite. Although existing grading rules can be used to grade recycled lumber and the general requirements for sizing, grading, and marking of softwood lumber have been established through the American Softwood Lumber Standard. Neither rules nor standards specifically address the use of recycled lumber or the characteristics that distinguish it from new lumber.
Many European counties have suPCCEssfully implemented deconstruction. Several key factors influence the suPCCEssful establishment of this practice. In general, European countries, governments, and individuals have some level of environmental literacy. These countries also lack the land needed to simply landfill mass quantities of waste. The lack of space for waste results in high disposal costs and therefore alternatives to traditional disposal are readily aPCCEpted. These alternatives tend to be progressive and inventive simply out of financial need and environmental awareness. Unfortunately these conditions are not mimicked in the US. Many factors in addition to those previously stated influence the establishment of a suPCCEssful deconstruction market sector. Factors such as population, tipping fees, existing supporting infrastructure, and building feedstock for deconstruction process all influence the potential for deconstruction. The existing support infrastructure or lack of infrastructure plays a key role in the suPCCEss of deconstruction. Barriers such as project time requirements, material and market variations, and land value must be overcome to provide suPCCEssful deconstruction implementation.
Used Building Materials
In the past decade, the use of reclaimed timbers has moved from a small industry into a mainstream construction market. Concerns for the environmental impact of construction are spreading among end users who are as diverse as first-time homebuyers to multinational corporations. Two major issues need to be addressed for suPCCEssful resale of these materials: cost and distribution. The bulk of the market is currently made up of those wealthy enough to pay extra to buy lumber from a very inefficient distribution and manufacturing system. The vast majority of individuals who identify with the green building concept do not feel able to afford reclaimed lumber.
For deconstruction to be profitable, the recovered materials must be sold in order to help defray the additional costs of hand labor associated with salvaging materials. Markets and uses for some materials, such as large timbers, metals, concrete, and fixtures – doors and windows, are established and therefore easy to sell. The estimation of materials to be recovered and the expected salvage values are critical in determining whether a deconstruction project will be financially viable. The continuing development of markets for salvaged lumber, especially smaller dimensions such as 2×4’s are needed and will have a great impact on the financial viability of deconstruction projects.
Contractors wishing to try their hand at resale of materials or possibly remanufacturing into value added products can realize economic growth from deconstructing. The facts are simple: there are good quality usable materials that can be recovered and turned into a profit if these salvaged materials are sold. The public misconception associated with the words “used” or “salvaged” must also be addressed.
7.1 Salvaged Quantities
It is difficult to determine the national quantities of buildings available for deconstruction. Based on information from the National Association of Homebuilders (NAHB), there are approximately 300,000 buildings demolished each year. The USDA Forest Service estimates that 3 trillion board feet of lumber could still be residing in existing structures. In looking at these numbers it appears nationally there exists a great potential and feedstock for the deconstruction industry.
Further investigation is needed on regional and local levels to determine area specific potential. For example, analyzing demolition permits, the Metro Portland area determined they could divert 944,000 board feet of lumber each year through salvage operations (Joslin et. Al., 1993). A similar study for the State of Florida would be an important measure of the true waste components specific to this region.
The average house has a lot to offer: toilets, sinks, tubs, cabinets, windows, doors, flooring, plumbing parts, and on average, 13,000 board feet of lumber. Disposing of these items via typical demolition results in price tags ranging from $500 – $2000 (Holmes, 1997). Once again seeing a low price tag shows only the costs specific to actual disposal. This cost does not factor in the environmental degradation associated with landfilling the materials or the production of virgin materials to replace them.
A project at Simcoe Place in Toronto teamed the Salvage Network with the Carpenters’ Union to remove the construction boarding from around a complete building. Historically, the majority of this material would have been damaged and sent to the dump. With some planning and skilled labor, over 350 sheets of ¾” plywood, 4100 feet of lumber, dozens of steel ceiling supports as well as massive wooden support beams were saved for reuse (EPA, 1998). The majority of this material was sold for profit.
An analysis of demolition permits in the Metro Portland regions showed that 944,000 board feet of lumber could be removed form the solid waste stream in the area each year through salvage operations (Joslin et. Al., 1993).
7.2 Used Building Material Associations
Used Building Material Associations (UBMA) are non-profit, membership based organizations that represent companies or organizations involved in the acquisition and/or redistribution of used building materials.
They represent for-profit and non-profit companies and organizations in Canada and the United States that acquire and sell used building materials such as windows, doors, and plumbing fixtures. The UBMA also represent companies that reprocess and recycle building materials such as concrete and asphalt. Their mission is to help companies gather and redistribute building materials in a financially sustainable way.
- Provide leadership for the removal of barriers that impede building materials reuse and recycling
- Increase availability of used building materials to the used building materials reuse industry
- Increase public, corporate and government purchase of used or recycled building materials.
- Provide guidance in the set up and operation of building materials reuse/recycling companies
- Develop deconstruction standards, codes of practice and/or guidelines
- Develop educational materials that will help individuals start or increase the efficiency of their building materials’ reuse/recycling company
- Lobby governments for legislative change and participate in policy development
- Help develop and promote building materials recycling/reprocessing technologies
- Develop a materials exchange information medium to assist in redistributing and /or acquiring used building materials.
Membership is open to any person who supports the guiding principles and who is the owner, operator, or authorized representative of a business that sells used building materials or that remanufactures or recycles used building materials. Others that have an interest in the industry and wish to support the efforts of the association, such as demolition companies, contractors, or government agencies, but are not directly involved in the industry may become an association member. Association members have all of the same benefits as members except they may not vote at annual and special meetings.
The UBMA’s hope to bring together companies and organizations to form a united voice to eliminate barriers in the construction industry and to help create opportunities to provide for growth.
|Case Study: Associations
Similar to the North America’s UBMA’s the Netherlands have a Belangenvereniging Recycling Bouw – en Sloopafval (BRBS) which is their form of a construction and demolition recycling industry association. The members of this association process approximately 95% of all construction and demolition waste that is processed. The objective of the association is to promote a good infrastructure for disposal of C&D waste and to ensure that materials produced are of high quality. The BRBS promotes the interests of its members and handles the contacts with the authorities and can therefore actively monitor legislation and regulations in this field.
In Canada there are many suPCCEssful regional operations that sell used building materials. On a larger scale, Happy Harry’s Used Building Materials is a good example of how the industry can deal with waste more proactively. Contractor/property manager Harry Bohna founded Happy Harry’s in Winnipeg. The company now runs 11 stores across Canada, organized as an owner-operated association. The chain recently opened their first Toronto store, with plans to add another 12 outlets throughout Ontario and Quebec within the next 14 months. The company is affiliated with The National Salvage Network, which enables the company to secure a steady supply of top quality used building materials.
The Salvage Network often works with conventional demolition companies to help recycle and reduce the waste from their projects. The rapid growth of the Happy Harry’s retail chain has dramatically increased demand for used building materials, and the company is now aggressively pursuing partnerships with other companies to source materials.
7.3 Markets and Resale
Selling materials from deconstruction sites can occur either on site or off site. By selling materials on site, deconstruction firms save valuable time and money required to move materials to another location. Selling materials on-site, even before deconstruction begins allows the deconstruction company to clear the site faster and collect sales revenue sooner. Identifying buyers for salvaged materials is a matter of extensive networking and marketing to identify who is interested in these niche materials. Architects, construction contractors, and do-it-yourself home renovators are obvious markets for lumber and fixtures.
For materials that can not be sold on site, deconstruction enterprises should establish partnerships with retail businesses like used building materials outlets and lumber yards so the materials can be transported off site and sold to the public elsewhere. Manufacturing enterprises can also use recovered materials to manufacture new products.
|Case Study: Outlet for deconstructed materials
Location: California East Bay Center for Creative Reuse, Oakland, CA
The center was started by school teachers to provide a source for low costs artists’ supplies. The project opened a reuse center and has since expanded to include artists making art from the salvaged materials and finding high end markets. Portions of the sales of the art goes to supporting the Center. The Center has a very serious business plan (cost $5,000) and has effective management. At this time the Center has $15,000 to $16,000 revenues per month. The experience of the Center was that goals should be established with fall back contingencies for every goal.
Several outlets exist for used building materials. If deconstruction is practiced on a small scale, one or two salvaged building material stores in one area would serve as a midpoint between deconstruction and reuse. However, for regional implementation a constant flow of materials is necessary. In order to achieve this flow, a network of contacts and are regularly updated list of materials available must be maintained. Used building material associations have the resources to provide this type of interactive network.
|Case Study: Markets for Deconstructed Wood
Location: San Francisco
Increasing demand for reclaimed lumber in the San Francisco Bay Area and beyond has strengthened markets for used and remanufactured wood products and has created the potential for new ones. Re-milled timbers and beams are typically used as structure in large, high end homes and in traditionally jointed post and beam construction. Re-milled dimensional lumber four inches in depth and smaller may be the broadest, most promising market. Using reclaimed wood for flooring, paneling, and siding turns average to difficult stock into fast selling products.
|Case Study: Materials Exchange
Location: Washington State
The Reusable Building Materials Exchange operates as a web based bulletin board where users can post available or sought materials. The Energy Outreach Center, a nonprofit organization in Washington State, devised the system that enables local governments anywhere to set up exchanges. Local governments offices or solid waste management jurisdictions can subscribe to the service on a sliding scale fee from $1,500 to $2,100 a year depending on population. Case Study: Material Reuse
Location: Washington DC
Burt Hill Kosar Rittelmann Associates, a Washington DC based firm “went shopping” throughout a 152,000 square foot building looking for reusable components prior to demolition. All the bathrooms in the building were being renovated to bring them up to ADA (Americans with Disabilities Act) codes. Rather than tossing the toilets and sinks, they were salvaged. Squares of new carpet left over from a previous renovation were later used in the basement and other locations in the building. Cork used as insulation in part of the building was reused in peg boards, storefront glass was salvaged and re-cut for storm windows, concrete demolition chunks were diverted from the landfill and used for landscape retaining walls and as structural / non-structural fill.
7.4 Wood Reuse
Lumber poses a special issue when its reuse is desired for structural applications. Appropriate quality control levels, grading, efficient denailing applications and using the material in structural applications are actively being pursued.
The practicality of recycling lumber depends on establishing viable reuse options. Ideally lumber should be used for the same function, i.e. a joist removed being a joist in a new structure. However, the options for reuse are restricted by the amount of damage the piece has experienced throughout its service life and during salvage.
7.4.1 Creating Markets for Salvaged Wood
Several generalizations can be made about the lumber and wood products market as a whole. Lumber is a very price sensitive market and, as a commodity, has a fairly volatile price structure. The lumber market is quality sensitive and has a well-established system of grading in place. Finally, like most products, the lumber market is convenience oriented. The average contractor likes to buy lumber within a fifteen-mile radius from the job site. The average homeowner likes to stay within three miles of home. Specialty wood will lure people a little further, but only if quality and price are also attractive (Falk, 1999). This is especially the case when considering consistency of supply. An important consideration in the reclaimed wood market is the limits on quantity and quality that are created by a variation in supply.
The market for deconstruction changed as demand for large wood members (6×6 and larger) became greater and consumers become willing to pay for the full cost of deconstruction. Increase in demand continues and is created by many factors including growing environmental awareness, higher prices and lower new lumber quality brought on by over-harvest of our old growth resources. Although in some cases slow to catch on, most demolition contractors now actively participate in the wood reuse market to some extent. In the Pacific Northwest some demolition contractors have begun to base their businesses on deconstruction creating their own line of reclaimed lumber products.
The demand for large old growth timbers has always existed, however the demand for smaller dimensional lumber is expanding. Historically there has been little demand for smaller dimension lumber – lumber with dimensions 4 inches in depth and smaller. Previously the demand was for larger timber. As those timbers have disappeared, the vast quantities of smaller dimension lumber available are beginning to drive the small dimension market. The growth trend of reclamation and sale of smaller, dimensional lumber has large implications for the overall reclaimed lumber market. This trend is helping to make new inroads with middle-income consumers, as many small dimension sizes can be used “as is” for common projects. The reclaimed lumber products market as a whole is connected to, but not entirely the same as, the deconstruction market. The reclaimed lumber products market has been both driven by the increased demand and been the catalyst for it. Reclaimed wood markets fall generally under two categories: primary wood products and value added or secondary products.
One issue with the reclaimed lumber products market is the societal expectation that reclaimed lumber be higher quality than new lumber. Although the bulk of reclaimed lumber is of good quality, only about 25% of the reclaimed lumber supply is of a quality unavailable on today’s new lumber market.
7.4.2 Value Added Manufacturing Enterprises
Flooring can be produced from material ranging from clear, vertical grain, to naily grade, flat grain if marked and priced appropriately. Very durable parquet flooring can even be produced from properly dried and milled cross sections of waste end cuts. Lengths as short as three feet can be utilized if the millwork equipment is sufficiently modern. This range of usable material allows a great deal of otherwise difficult to use stock to be made into fast selling, value added products.
Paneling and siding products can be produced with a very average grade of lumber and are also fast selling items when made available through good distribution. Siding is generally produced from longer lengths (8 foot minimum), but paneling can have shorts mixed in a random length package or be produced entirely from shorts. They, too, are good candidates for an integrated mill product because they are so universally used in construction and can be produced from a wide variety of materials. All of these products can be manufactured by a less than state of the art facility using standard patterns. This makes them inexpensive to produce, relative to the value added.
18.104.22.168 Architectural Millwork
Manufactures of architectural millwork prefer wood that is clear stock with minimal defects, dry, and dense old-growth. Although it may be difficult to reclaim lumber without defects, the density and low moisture content of the salvaged materials is highly desirable. Producing the millwork itself is expensive, however supplying the wood to others is a potential market.
22.214.171.124 Furniture, Small Manufacturing Items, Custom Doors
Custom furniture makers prefer to choose the best and hardest possible materials that are often not salvaged lumber, however the retail arena offers some options. Custom furniture built-ins made from reclaimed wood are popular in retail stores. Small manufacturing items may be produced from salvaged odds and ends providing the market will support a variety of items. Custom doors provide an excellent opportunity to reuse lumber. Doors can provide a high value use of short clears and can also be produced from naily grade lumber.
7.5 Salvaged Wood Properties and Re-Grading
One of the main barriers to the widespread reuse of smaller dimensional lumber is the lack of up to date grading or certification stamps. Framing lumber salvaged from older buildings may have either a lumber grade stamp that is no longer aPCCEpted by local building inspectors or lack any lumber grade stamp at all. Grade stamps on salvaged lumber may be invalidated by alterations to the lumber, (drilled holes, notches, checking, through-mail penetrations, etc.) or simply by age.
The use of salvaged building materials without proper stamps is a violation of code, inspectors simply will not sign off on materials that are not properly graded. Currently the re-grading of salvaged wood is not common. Many consumers are hesitant when purchasing wood for any applications when the wood lacks certification. Currently, salvaged lumber can be used in non structural applications. A grading system for this salvaged wood would drastically increase its usability. It is unclear when, if at all, lumber grade stamps can expire. Many lumber graders have been reluctant to re-grade salvaged lumber because they feel they lack background information and a methodology to follow on the structural performance of lumber that has been under load for an extended period of time. The USDA Forest Products Laboratory is currently performing structural tests of salvaged lumber in an effort to provide guidance on this issue.
Evaluating recycled lumber with existing grading rules may not result in the most efficient use of this resource. Existing grading limitations for certain characteristics – checks and splits – were developed for freshly sawn lumber. It is not clear to what extent these defects affect recycled lumber engineering properties and subsequent reuse options.
The University of Florida is also performing some mechanical property tests on lumber salvaged from several homes deconstructed in the Gainesville area. These tests are destructive and will determine the strength of the salvaged materials. The testing is in an effort to compare post salvaged visual inspection with the corresponding flexural breaking strength. The strength of the salvaged materials will also be compared with current standards for dimensional lumber.
|Case Study: Mechanical Properties Testing of Reclaimed Wood
Location: Twin Cities
In 1995 lumber and timber was collected during the dismantlement of building 503, a large wood framed industrial building belonging to the US Army. This 548,000 square foot heavy timber building contained approximately 1,875,000 board feet of softwood timber, primarily Douglas fir. Research staff and the USDA Forest Service , Forest Products Laboratory (FPL) worked cooperatively with US Army facilities engineers and demolition contractors at the TCAAP to select a limited amount of lumber and timber members for testing. Approximately 35,000 board feet of lumber and timber were collected from building 503. The lumber collected included 2×10’s, 6×8’s, 8×8’s, 6×14’s, and 10×18’s.
The lumber was separated into two groups; Group 1 contained 500 pieces to be graded on site and Group 2 contained 100 pieces that were shipped to the Forest Products Lab. (Prior to testing it was believed all of Group 2 was Douglas fir – upon inspection, 53 were identified as Douglas-fir and 25 as Hem-fir).
Since the original sample size of 100 pieces was not all the same species conclusions from the data are not statistically accurate.
Although the sample size that was available in the study was small, the testing and analysis indicate that this lumber has potential for reuse in construction applications. Stiffness of the lumber was found to be approximately equal to that of current production, however, the strength was less than expected. (Strength characteristics were possibly a result chemical contamination during the life of the building).
Further research is needed in this area to develop a grading system specific and useful to salvaged lumber. Studies such as the one above are the beginning of data collection needed to determine the regrading standards.
7.5.1 Lumber regrading
Because no standards exist for the regrading of salvaged lumber when lumber is regraded, it is often regraded according to new lumber standards. Since salvaged lumber has many characteristics that do not fall into a category of grading – such as nail holes – salvaged lumber is often graded lower than needed. The current process for wood regrading is fairly time consuming. This process is not recommended or cost effective for small quantities of salvaged lumber.
The first step in the regrading process is to identify the local grading agency. These agencies are based on region and must be accredited by the Board of Review of the American Lumber Standards Committee. The Southern Pine Inspection Bureau, Inc. governs the State of Florida. The Southern Pine Inspection Bureau has general specifications on re-grading lumber that have not been revised in seven years. The wood re-grading is a visual inspection – studies are underway using mechanical testing means to determine if the properties of the wood have statistically changed during the loading period. The Southern Pine Inspection Bureau has several disclaimers regarding the re-grading process. Their standard disclaimer is “they do not re-grade wood to be sold and used for structural lumber.” However, the popularity of reusing lumber is rising and the agency is being pushed to comply with consumer demands. In addition to the inspection bureau the local agency responsible for stamping wood must be contacted. This agency can be identified by contacting the American Lumber Standard Committee or the National Grading Regulation (NGR) agency. Each region accreditation agency writes individual regrading standards. These standards are specific to the agency and the region. Due to these standard differences it is possible for the same stack of lumber to be regraded indifferent regions and receive different grades.
After contacting the appropriate agency, an inspector must be sent to regrade the wood. The wood should be covered from the elements, bundled by length, similar in dimension and unpainted. A few weeks lead time is required for the inspector. The wood will not be re-graded if the moisture content is above 19%. If the grader must travel the cost in Florida is $225 per day plus expenses. It is possible for the inspector to grade about 15,000 board feet per day with the assistance of a wood handler and organized wood piles. Once the lumber is regraded, the ultimate use of the lumber falls under the jurisdiction of the local building code inspectors. Both the inspection bureaus and the local building code inspectors fear the liability associated with approving the use of salvaged lumber. The liability is associated with certifying the strength of salvaged or reclaimed lumber. There currently is not enough information regarding the effects of age and use on wood strength to provide thorough guidelines. Research is currently being conducted by the US Forest Products Laboratory to determine these effects to assist in establishing these guidelines.
For the past thirty years the wood products industry has been retooling to use smaller, lower quality log stock as smaller younger trees replace the old growth supply. The lumber market today is a combination of wood particle products, laminates, composites and engineered wood products. The current trends in the new wood product’s industry strongly dictate both the markets and manufacturing opportunities available to the reclaimed wood products industry. These trends also provide some interesting marketing opportunities for reclaimed lumber. Glue laminated beams and engineered truss joists often take the place of reclaimed lumber products because of their superior strength, performance, and lower overall cost. Alternately, the new markets for large timbers and beams, dense grain material, heart redwood, clear grades of pine and Douglas fir are struggling due to lack of supply. These are the markets to which reclaimed lumber has easy entry and traditional suPCCEss.
The sustainably harvested industry relates to the reclaimed industry in many ways. First, outlets that sell sustainably harvested wood are often interested in offering reclaimed wood to augment their softwood products. The sustainably harvested industry also helps to spread awareness about the importance of buying wood that is ecologically low impact. At times the two products compete with each other and sustainably harvested wood does offer the customer the advantage of a long term source for ongoing projects and products and unblemished with fastener marks. However, since sustainably harvested wood is often second-growth, the overall innate quality of reclaimed lumber is usually superior.
There are approximately 300,000 buildings demolished each year. This results in massive quantities of potentially reusable materials being landfilled. The potential exists for reuse of these materials with appropriate marketing and resale. The establishment of used building materials associations can greatly assist in reuse of these materials. Some issues regarding the structural integrity of reclaimed wood exist, studies are currently underway to determine structural properties of reclaimed materials.
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Falk, R. H., Green D., and. Lantz,S. C. Evaluation of Lumber Recycled From Industrial Military Buildings. Forest Products Journal, Vol. 49, No. 5. May 1999.
Florida Department of Environmental Protection (FDEP), Bureau of Solid and Hazardous Waste Division of Waste Management. Solid Waste Management in Florida. Tallahassee, Florida, June, 1998.
Franklin Associates. Characterization of Building-Related Construction and Demolition Debris in the United States. A report to the U.S. Environmental Protection Agency Office of Solid Waste and Energy Response. Washington, D.C., June, 1998.
Gadh, R. Industrial Design for Environment Via Design for Disassembly – An Automotive Focus. Environmentally Conscious Manufacturing, 1997.
Hanrahan, Pegeen. Construction and Demolition Debris Disposal Issues: An Alachua County Perspective. Alachua County Environmental Proteccion Department. Gainesville, Florida, 1994.
Hendriks, CH. F., Kowalczyk, T., Kristinsson, J. Decision Support Model for Dismantling an Existing Building into Reusable Elements or Components, 1998.
Holmes, Hannah. Bringing Down the House. Hearth & Home, September/October 1997.
Housing Deconstruction Report. By design Consultants. Ottawa, Canada. 1997.
Jefferson Recycled Works. Overview of the Market for Reclaimed lumber in the San Francisco Bay Area. Materials for the Future Foundation. November, 1997.
Johnson, Huey D. Green Plans in the US Interior Concerns Newsletter Information on Sustainable Design, Building and Development, September/October 1996, pp. 8-9.
Joslin, Jeff, Phil Kreitner and Bill Welch. The Waste Papers: Analysis and Discussion of the Potential for Salvage and Re-Use of Construction Materials from Residential Demolition. Whole House Recycling Project. Metro Service District. Portland, Oregon, 1993.
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This section examines the total costs associated with the deconstruction process. There are many hidden factors that account for the true cost of a process. Unfortunately, society and builders currently are not exposed to the true cost associated with the deconstruction process. For example, the most common form of structure removal is demolition. Several factors lead to this domination of the market. Demolition is quick and inexpensive. Although little can be done to completely bridge the time gap between deconstruction and demolition, many deconstruction projects have been conducted and proven to be profitable. Deconstruction can prove to be far more profitable than demolition if environmental costs are considered. Benefits from deconstruction include the reduction in the use of landfill space therefore prolonging landfill life. The reuse of salvaged building materials offers may environmental and cost advantages.
The environmental costs associated with the raw material extraction, transportation, energy to mill, transportation to seller, cost to buyer, transportation to site were all factored in, the salvaged building materials would appear more appealing. Due to highly publicized niche materials markets there is a current perception that reclaimed materials are much pricier than new standard construction materials or of lesser quality. Although some reclaimed materials have spurred high price niche markets, the majority of the reclaimed materials are perfect for direct reuse. In Vancouver, Architects Busby & Associates set a goal to construct their new building from 95% recycled materials and did so without compromising the budget.
|CASE STUDY – Total Cost
LOCATION – VancouverReclaimed Timber yields quality building at competitive priceA new asphalt testing plant was constructed almost entirely of recycled lumber salvaged from warehouses on site that were slated for demolition. The building Architects (Busby & Associates) believed that a higher quality building could be constructed from 95% recycled materials at a competitive price. The warehouses’ heavy timber trusses, glulam purlins and tongue and groove decking provided most of the structural material for the new testing plant. Doors, windows and plywood sheathing were purchased through salvage companies at prices between 10 and 50 percent of the cost of new material. The project met budget and recycled material targets.
When the right buildings are selected, the cost of deconstruction is less than or similar to the cost of demolition because additional labor costs are offset by the sale of salvaged materials and avoided disposal fees. However, goals such as using trainees rather than experienced workers and pushing recovery rates to the maximum can extend project timelines and raises costs above those for demolition. Labor costs are typically the largest portion of a deconstruction budget. The labor cost variable is based on several factors such as the size and type of structure, the skill level of the crew, and how easily the materials can be removed. The value of salvaged materials and remaining material requiring demolition and disposal also affect project expenses and revenues.
Many cities are looking at deconstruction as a way to address their abandoned housing problems while creating job training and employment benefits, often at the same cost or less than traditional demolition. According to one developer in the Mid-Atlantic region, it costs $14,000 to deconstruct a small abandoned house as compared to $16,000 to demolish it.
8.1 Case Studies
Ignoring the economic driving factor and assuming total deconstruction is the goal, we will use case studies to determine the cost of deconstruction. Most of the case studies had funding from an outside institution to make possible the collection of data. Due to this influence – the case studies do not accurately represent field conditions. For example, a deconstruction contractor would not have to establish a data collection station on site and collect data. Financial payback on construction salvage varies. By recycling and reusing building materials on one of Portland Oregon’s $1million renovation project, $30,000 in construction costs were deferred, and $10,000 were saved by avoiding landfill fees (EPA, 1997). Research from the Riverdale Case study documented the time required to manually disassemble and salvage/recycle/dispose of 25 different building materials. (NAHB, 1997) Total cost comparison – standard demolition was estimated at $3.50 to $5.00 per SF. Total cost for deconstruction was estimated at $4.50 to $5.40 per SF (NAHB, 1997).
In looking at cost data collected on the Presidio building #901 and the Port of Oakland building #733 – shown below – in both instances the net cost of deconstruction was far less than demolition. Deconstruction resulted in a 45% and 66% savings over demolition in buildings #901 and #733 respectively. As expected the labor costs were the largest portion of the expenses at 62% for building 901 and 82% for building 733.
|Case Study: Deconstruction Cost
Location: Presidio, Building #901
The following case studies from Gainesville, Florida look at the costs and benefits of 3 projects ranging from complete hand deconstruction to total mechanical demolition. All of the houses were bid and awarded at $2.16 per square foot. The first house was completely deconstructed. The second house was partially manually deconstructed and the remaining portions were then mechanically demolished. The third house was completely mechanically demolished. Since all homes were bid at the same cost per square foot, the goal was to determine, based on total cost, the most profitable building removal method.
The first case study house (625 NW 4th Street) was a 816 square foot wood stud framed construction building with exterior novelty siding and interior siding composed of 1 x 4 planks and beadboard. Roofing was 5 V-crimp metal installed over purlins and wood rafters. This house was completely hand deconstructed.
|Case Study: Total Hand Deconstruction
Location: Gainesville, FLThe project costs are listed below. This house was bid and awarded at $2.16 per square foot or $1763.
The deconstruction of this home resulted in approximately 16.7 lbs/SF of waste being sent to the landfill. The labor and processing combined accounted for 68% of the total hours used to deconstruct the house. This project diverted over 76% of its potential waste stream.
The second house deconstructed (629 NW 4th Street) used the combination of hand and mechanical demolition. This 710 square foot house was a single story wood-framed building with wood exterior and exterior siding and a metal roof. It was on raised brick piers and had several additions to the original structure.
|Case Study: Hand and Mechanical Deconstruction
Location: Gainesville, FLThe combined use of hand and mechanical deconstruction proved to be more cost effective than complete hand deconstruction. This house was bid and awarded at $2.16 per square foot or $1534.
The deconstruction of this house resulted in 28.7 lbs/SF approximately 50% more waste was produced in this process
The third house located @ 633 NW 4th Street was similar in composition and age to the first two structures and had a floor area of 750 square feet.
Several lessons were learned from these three similar structures. The mechanical demolition resulted in a loss compared to the two houses that incorporated some form of deconstruction. The demolished home however, took far less time to remove. In some respects less time to remove the structure is beneficial, i.e. often for contractors, but the deconstructed structures were able to employ individuals for a longer duration and still turned a profit. The benefit of providing jobs for the community is difficult to quantify. Although mechanically demolishing homes was faster, the amount of waste sent to the landfill was 4.3 times more than the amount from the completely deconstructed home.
This Maryland case study reported half of the labor requirements were needed to physically deconstruct and the second half were needed for processing of material.
|Case Study: 2,000 square foot residential building
Location Baltimore County, MarylandA detailed inventory was conducted at the outset to determine how the building was made and of what materials. All components of the building from roof to foundation were quantified and their condition assessed. NAHB found this to be the most important part of assessing the feasibility of deconstruction for a particular structure.Half of the labor required was for disassembly and half for processing (nail pulling, sorting, and stacking). NAHB concluded that: manual disassembly of light-framed (low-rise residential) buildings represents and excellent opportunity to identify and develop low skilled workers with an aptitude and interest in the building trades. Deconstruction may also represent welfare to work and small business opportunities.Total costs of the project were estimated at $9000 to $11000, compared to demolition estimates of $7000 to $10000.Materials reuse accounted for 30 percent by volume and 23 percent by weight. Diversion from landfill (both reuse and recycling) was 70 percent by volume and 76 percent by weight.
Deconstruction projects often are very difficult to estimate in terms of time. It is important to understand that this variable must remain flexible to make deconstruction work. Until the deconstructing process has begun the contractor may be completely unaware of what lies under the finished surface of the structure.
A wide range of environmental, regulatory, worker, and logistical issues must either be addressed prior to the start of work. These are issues that will affect the overall process of building removal. Many factors affect the actual cost of deconstruction. In addition to the obvious factors such as labor and tipping fees, additional knowledge and capital are imperative in the following areas as well.
8.2 Cost Factors
Planning: Deconstruction is a tried and true practice. However as in new construction and demolition every structure is unique. It is necessary to thoroughly evaluate each project, try to anticipate problems, expect surprises, and prepare for delays. Proper planning can make most deconstruction projects valuable and profitable.
Training: Although deconstruction is not a highly skilled technological task, the process requires a certain amount of finesse and coordination. Knowledge of construction techniques and the construction process will assist in the “reverse construction” of the structures. Training can teach disassembly techniques and proper handling of hazardous materials.
Labor: Deconstruction is extremely labor intensive. Almost all of the work requires manual labor. Due to labor cost variations throughout the region, this will be a key factor in the financial suPCCEss of deconstruction projects.
Material Collection: The nature of deconstruction results in a separation of materials as the structure is disassembled. These materials must be collected and cared for to receive the highest possible salvage price. Materials are not thrown as heaps into waste bins as in traditional demolition.
Sorting: As the materials are removed from the structure and collected they should be sorted according to materials type and dimension.
Inventory: It may be necessary to take an inventory of the material for future sale. By sorting the materials into like items, the inventory of materials is somewhat simplified.
Storage: It is unlikely that the materials salvaged from a project will be sold the day they are removed from the structure. The collecting, sorting, and inventory of these materials will aide in receiving the highest possible revenue from their sale. It is important to note that all of these actions involve the addition of man-hours to the cost of deconstructing.
Grading: Currently the reuse of salvaged lumber is limited to non-structural applications. As discussed in Chapter 7 wood can be regraded at an additional cost. Research is underway to establish reuse and regrading guidelines. The USDA Forest Products laboratory is exploring specifically the re-grading of lumber for reuse in load bearing applications
Transportation: It is most likely that the storage facility will be centrally located to the deconstruction company and not the deconstruction site. For this reason transportation of materials will be necessary.
Resale: – The resale value of items varies throughout the region – resale marketing options are found in the Lessons Learned section of this report.
8.3 Labor cost and availability
Nationally the construction trades are experiencing a labor shortage – mostly due to the low interest rates, a booming economy, and unpredictable construction activity. This growth has resulted in a national shortage of trained construction workers. Although workers do not need extensive training for deconstruction, the persons employing the workers by far can reap more benefit financially from sending their crews to construction sites versus deconstruction sites. It takes only a few workers a matter of hours to demolish a structure, whereas it takes a crew several days to several weeks to properly deconstruct a building. Starting deconstruction companies do not require large capital cost for equipment which can make the process attractive to beginning deconstructors. Unfortunately, current market conditions simply do not allow for what industry sees as a waste of labor. Industry perceives the labor spent on deconstructing as a waste because the cost of disposal is extremely low when compared to labor. If disposal costs were to increase industry would need to reevaluate their current allocation of resources. Until deconstruction is a cost and time effective alternative to demolition the widespread implementation is uncertain.
The actual cost of deconstruction also has many significant influence factors. Location seems to be one of the key factors. Location dictates disposal cost, labor cost, regulations, existing infrastructure, and attitude. Full cost accounting of building materials and their true environmental impacts throughout their lives would prove keeping the deconstructed materials in service is much more cost effective than disposal. However, this method is not employed and therefore the true value of the salvaged materials are unknown. All of the case studies examined show that deconstruction can be a profitable undertaking, however specific regional influences must be examined.
Although the specific process each individual or deconstruction crew follows will vary, these are some key steps and processes that have been developed from case studies and experienced deconstructors. The following provides an outline of the deconstruction process. Prior to beginning any process with the structure itself, it is important to investigate any permitting issues specific to the region.
9.1 Permitting Process
Many but not all local building jurisdictions require demolition permits or formal notification of intent to remove a building. Approval of the demolition permit will often be linked to disconnection of electrical power, capping of all gas and sewer lines, and abatement of hazardous materials such as lead and asbestos. In most regions where deconstruction is not an established or well known alternative, there will probably be no difference between the procedure required to obtain a permit for demolition or deconstruction.
|Case Study: Permitting Process
Location: Gainesville, FLIn Alachua county there is no regulatory distinction between demolition and deconstruction. The City of Gainesville requires a demolition permit for all demolition within the City limits. It also requires all general contractors secure a business permit for work in the City limits.
Although the city of Gainesville has no distinction between demolition and deconstruction the city has a 90 day delay for demolition. This delay applies to all structures not in a designated historic district. The required 90 day delay allows the city to post a pubic notice at the structure which advertises the structure is free to anyone who will pay to move it.
If the city were to allow deconstruction during this 90 day waiting period the time factor associated with the deconstruction process would be nullified. The fact that a structure could be deconstructed faster than demolished would allow owners faster use of their property which is often a key driving factor for demolition. In this respect the permitting process could act as an incentive to deconstruct.
9.2 Building Assessment – Building material inventory
While deconstruction is not the answer for every building that needs to be removed, it is certainly applicable to many structures, especially older buildings. The following indicators can be used in determining if a structure might be a good candidate for deconstruction.
- Brick buildings built before 1933
- Structures containing old-growth or rare wood species
- Interesting or high-quality architectural features
- Hardwood floors
- Large timbers
- Large quantities of unpainted wood
Other factors used to assess the extent to which a building can be deconstructed include:
- Age of structure
- Type and condition of materials in the structure
- Methods of construction, these will impact the ease or difficulty to recover materials
- Availability of recycling options for materials that cannot be reused.
The most important part of determining feasibility is using a detailed inventory of how and what the building is made of. Document every component and how it is secured. This inventory should be done using an invasive inspection of the structure if possible. The inventory not only gives the deconstructor an idea of how to disassemble the building but also is the starting point for determining whether or not it is possible to turn a profit.
|Case Study: Residential Building Assessment
Location: Gainesville, FloridaAs an example of a building assessment, a deconstruction supervisor in Gainesville evaluated the overall condition of a home including the structure and building materials. The structure was rated as excellent in the building’s initial assessment and inventory. This was principally due to the integrity of the building envelope. Rot and wood-boring organisms were found in limited instances, principally in the kitchen and bathroom where water and stagnant air are common. The roof had an unusually steep pitch of 10:12 and was constructed of two layers of roofing, an outer layer of 5-v crimpt metal roofing and an inner layer of asphalt shingles with some fire-damage.
The more detailed the building assessment, the more accurate the estimate to deconstruct the building can be. The income from salvaged materials must be considered to lower the deconstruction bid to beat out demolition bids. This assessment should include items such as if the home appears to have lath and plaster walls, the type and square footage of flooring, number of windows and doors and any distinctive features. If it is possible, find and analyze the original plans for the structure. Analyzing the rough and as-builts for the structure also assist in the deconstructors evaluation of the structure. This initial building assessment will lead to the environmental assessment.
Whether demolishing or deconstructing a structure, hazardous materials – mainly asbestos, lead-based paint, and chemically treated wood – are a concern in many facilities. The presence of these materials requires special handling and disposal regardless of the process used to remove the structure. Proper handling of hazardous materials results in additional cost. Due to these additional costs, often demolition contractors overlook proper handling of hazardous materials. Some materials contaminated with lead-based paint and chemicals that prevent wood from rotting can be handled directly by the deconstruction contractor, however, asbestos abatement, must be handled by a licensed asbestos abatement contractor.
Deconstruction as well as demolition contractors will regularly come into contact with hazardous materials while removing a building. For example, materials such as lead-based paint, chemically treated wood, asbestos, mercury switches, and PCB ballasts. Although both deconstruction and demolition crews come into contact with these materials, deconstruction crews are dealing with the hazards using a more hands on approach for longer periods of time. For this reason appropriate measures to ensure worker safety are needed.
Structures built before 1978 and especially those built before 1960 most probably contain painted wood that contains lead. Crews should be trained in the best ways to minimize flaking the paint off the wood and creating lead dust during deconstruction. These practices include avoiding the use of power cutting tools, and excessive hammering and scraping on leaded surfaces and the exclusive use of tools like pry bars and mallets to take leaded lumber apart. Regulations concerning the use of and disposal of lead-painted wood vary across the country.
Asbestos containing material (ACM) is assumed to be in any structure built prior to 1980 and lead-based paint (LBP) is a hazard to be found on any home older than 1980. Browning Environmental Service Technologies, Inc., Gainesville, Florida was contracted by the deconstruction contractor, Sustainable Efficient Construction, Inc. to perform lead-based paint (LBP) and asbestos containing materials (ACM) surveys on the structure, before any deconstruction activity took place. Samples taken from all suspect, homogeneous ACM and LBP surfaces. Polarize Light Microscopy with dispersion staining were used to analyze the ACM samples using US EPA Interim Method for the Determination of Asbestos Minerals in Bulk Materials. LBP samples are tested using the NIOSH Method #7082.
9.3.1 Asbestos Abatement
There are two sets of federal regulations involved in the management of asbestos: Environmental Protection Agency (EPA) and Occupational Safety and Health Administration (OSHA). The EPA rules for asbestos contain no language that would require different hauling and disposal procedures for deconstruction and demolition. The abatement of asbestos containing floor tiles and roofing shingles prior to demolition or deconstruction activity is not required by EPA. By contrast, OSHA rules for worker exposure to asbestos could place a greater burden on deconstruction than demolition.
9.3.2 Lead Abatement
Both EPA and OSHA have rules governing the management of lead-based paint in buildings. The language of EPA disposal regulations makes no distinction between a deconstruction and demolition approach. OSHA rules identify manual demolition of any material containing lead as an activity that is presumed to require lead exposure worker protection measures, regardless of absolute levels of lead in painted surfaces.
OSHA and EPA both recognize that deconstruction is a less invasive destructive process than mechanical demolition, but conversely that it has the potential for greater exposure by workers to ACM and LBP. The following protocol has been established for deconstruction in an interior LBP environment:
- All workers receive an ACM and LBP awareness approved training course.
- All exterior windows and doors are opened or removed to allow ventilation and prevent accumulation and concentrations of LBP particulate matter during deconstruction activities.
- All workers in the LBP environment are provided personal fit-tested and approved respirators and protective clothing until personal air samples are analyzed and record lead levels below the aPCCEptable threshold for worker exposure.
- A HEPA vacuum is utilized throughout the building interior to remove all dust and particulate matter to the maximum extent feasible.
- Indoor air quality analysis is completed using approved personal air sampling devices to determine TWA-PEL of lead within the work environment.
- At such time as air sampling is recorded which shows airborne lead levels below OSHA thresholds, respirators and protective clothing will be removed.
- In all cases, workers will be rotated out of LBP environments on a short-cycle and regular basis.
- Job-site hand washing station will be provided.
- Smoking is prohibited inside the structure and near any salvaged materials. Workers are required to wash hands before breaks and lunch breaks.
- Sanding, cutting, grinding, abraded, burning and heat-gun stripping of LBP surfaces is not permitted.
- Workers are provided with uniform T-shirts and required to change them at the completion of the work shift and before leaving the job-site.
It is the responsibility of the property owner to make a reasonable effort to identify hazardous materials on the site prior to demolition or deconstruction. This would include a visual non-invasive inspection of all aspects of the site and structure by an individual trained in environmental assessment. If hazards are identified, further investigation is necessary. (Industry standards for environmental assessment are set out in ASTM 1527-94 or 1528-94). In one of the houses deconstructed in Gainesville, materials were analyzed to determine if any of the materials were potentially hazardous. Samples of tile were collected to determine the presence of potential hazardous materials. This process is shown below in Figure 7.
As seen in the list of asbestos containing materials, there are many home components that may contain asbestos. In addition to floor tile, some ceiling and wall coverings also may prove to be a source of potentially hazardous materials. Due to the hands-on nature of deconstruction, worker safety is a primary concern. All precautions should be taken to ensure limited exposure to hazardous materials. Figure 8 shows the asbestos sample collection process for wall specimens.
In addition to asbestos, lead paint is especially a hazard for homes constructed prior to 1960. Samples of paint are collected to test for lead levels, care is taken to minimize dust particles created during the collection process. Figure 9 shows collection of a paint sample for lead testing.
|Case Study: Asbestos Abatement and Lead Paint Protocol
Location: Gainesville, Florida
The samples in Figure 7, 8, and 9 were analyzed by EMSL Analytical, Inc., Program, Greensboro, NC. Non-friable Category I asbestos was found in vinyl floor tile in two locations in the building. Vinyl floor tile in the kitchen contained 2 percent chrysolite and vinyl floor covering in the bathroom and south porch was found to have 40 percent chrysolite content.
No interior LBP samples were determined to exceed aPCCEptable levels for human exposure. LBP samples from the exterior siding were found to contain from 9.19 to 9.90 percent lead content. The ACM vinyl covered tile and mastic in the kitchen, bathroom and south porch additions was abated by a certified asbestos abatement contractor, Merit Abatement, MacInney, Florida. Worker LBP exposure for the exterior siding was deemed to be within aPCCEptable levels due the non-destructive nature of the hand deconstruction and 100% ventilation on the exterior of the structure. There was no sanding, grinding, abrading, cutting, burning or heating of the LBP wood materials. The primary threat of worker exposure to LBP was through ingestion – eating, drinking and smoking while in proximity to the LBP. A hand washing station was established on the job-site and personal protective equipment (gloves) was required of all workers. All workers received asbestos and lead awareness training before being allowed on the job-site. The training was provided by the University of Florida’s Center for Training, Research and Education for Environmental Occupations (TREEO Center) and was in compliance with OSHA’s asbestos section 29 CFR 1926.1101 and lead section 29 CFR 1926.62. The purpose of the training was to expand worker awareness of lead and asbestos issues.
9.3.3 Hazardous characteristics
Workers – Fall protection, maintenance of structural integrity, and fire prevention are three issues that must be considered during deconstruction that are often less important during conventional demolition. OSHA requires the use of certified harness and belay systems for all but flat roof work. Maintaining structural integrity requires an experienced building professional. In addition to these three key issues, hazardous materials are a primary concern.
9.4 Field Safety
The job-site superintendent coordinated field safety education and performance. All workers should have work boots, long pants, shirts, safety glasses, hardhats and gloves for protection. Cleanup of debris on all work surfaces occurred after each phase of deconstruction. Piles of debris were not allowed to accumulate in work areas where they could generate a hazard or impediment to the workers.
9.5 Workers Compensation Insurance
Unlike some industries that have a single classification code for all or many of their workers, premiums for construction and demolition workers compensation insurance are based on the actual individual tasks performed during the work day. It is critical that deconstruction firms explain the nature of their work to insurance agents so that coverage and resulting premiums reflect the level of risk for their workers activities.
Time constraints – Deconstruction in almost all cases requires significantly more time than demolition. Building removal is in many cases done under very tight time constraints. For a property owner with plans to redevelop after building removal, time is money.
9.7 Jobsite Preparation
Areas should be cleared for parking, a denailing station, and dumpster locations.
9.8 Site Map of Deconstruction Field Organization
The following diagram Figure 10 is an example of how a site could be set up from a deconstruction point of view. It is important to note that every deconstruction site will differ in space allocation. The key points of the site set up include the denailing and processing station is located between the “Loading Area”, and the dumpsters. If it is not possible to arrange the site in this way the processing station should be located in close proximity to the storage and disposal sites.
When materials are removed from the structure the determination must be made on what to do with the specific material. Most materials fall into three main categories.
- Immediate Reuse
- Process Further
- Dispose of
For this reason it is important to have the storage space, processing space, and dumpsters close to the structure. Having the processing station between these two stations allows for an easy flow of materials. If processing destroys the material or if it is determined that it is not cost effective to further salvage the material it can be regrettably but easily put into the dumpster.
In the North Central portion of Florida it is highly unlikely that a massive structure containing old growth timber will become available for deconstruction. A deconstructor is more likely to find an older somewhat dilapidated structures in need of removal. The following is a summary of the steps and processes that the Powell Center for Construction and Environment used to deconstruct a home in Gainesville Florida. This home had two areas that contaminated by asbestos: the siding and the interior tile. The owner abated the siding prior to the following process. Of additional interest the following work was conducted during the summer. The heat index for all of the following days was well above 100o F.
Site Cleanup and House Cleaning: The first day on the project site was dedicated to house and site clean up. The property was abandoned and as a result the site and home were scattered with debris. The site was cleared to allow adequate space for the dumpsters and the denailing/processing station. All remaining interior furniture was removed to allow workers undisrupted aPCCEss to the interior structure. In addition, No Trespassing signs and job-site signs were posted.
Asbestos Tile and Mastic: On the second day the abatement contractor was on site for hazardous material removal. The full abatement of hazardous materials was necessary prior to any deconstruction work.
Doors, Windows, Trim, Exterior Awnings: The deconstruction process began with the removal of all doors and windows. In addition to the doors and window, the associated frames and their trim pieces were removed. The doors and windows are maintained as a complete package so they may be resold in this manner.
Oak floor, Doors, Windows, Ceiling Fans, Baseboards, Crown molding: The home had oak flooring as a part of a 1952 renovation laid on top of pine flooring. The oak floor was carefully removed. Baseboards were then removed prior to the plaster and lathe. Past experience and experiments in the demolition of plaster and lathe indicated that it is better to break apart (smash) the plaster enough to loosen it from the lathe. This allows the plaster to be separated from the lathe for disposal.
Since deconstruction occurs in the reverse order of construction, the first few days activities include removing the finishing materials from the house. Interior materials such as baseboards, trim, and crown molding are removed. Figure 11 shows the jobsite after the baseboards and trim have been removed.
Plaster, Floor felt, lathe: Work continued on the removal of the wall plaster. As much as possible, the lathe was left in place attached to the stud walls. The lathe is much easier to remove if it is pushed off of the walls from behind as opposed to pulling it away from the wall. Under the oak floor, a floor felt under oak floor had been glued to the original pine floor. This was peeled up since it was secured with a water-based glue. Figure 12 below shows the removal of interior drywall or plaster and lathe being removed.
Lathe, sheet metal roofing, batt insulation, beadboard walls: The remainder of the lathe was removed. The insulation that was salvaged was given away the day it was removed to the community. The beadboard walls were removed. The removal of the roofing surface began. The sheet metal roofing was difficult to remove due to the 10:12 roof pitch of the original structure. Figure 13 shows the removal of roofing material.
1 x 8 roof deck, double layer of asphalt shingles, lathe, transfer plaster debris: The metal roofing was removed to reveal two layers of asphalt shingles. The shingles covered a 1 x 8 roof deck. To remove the roof deck, plywood was positioned on the ceiling joists to create a continuous work surface. The 1 x 8 roof deck was punched out from behind by crews of 3 to 4 standing on plywood decking. The age of the shingles resulted in the shattering of them as the 1 x 8 roof deck was removed. The shingles proved easier to remove at the processing station at ground level than up on the rafters. In addition to roof work, plaster debris loaded to the top in an 8 CY dumpster. When the garbage truck came to remove the full dumpster, the resulting weight of a full dumpster of plaster was too heavy for the garbage truck to lift. Workers have to transfer 4 CY of the plaster into a different dumpster. Figure 14 shows the roof structure once the roofing material and sheathing were removed.
2 x 4 rafters, 1 x 8 roof deck: The remaining 1 x8 roof deck was removed. The 2 x 4 roof rafters are also removed from 10:12 roof. Once the roof structure was removed, the stud walls can be dropped to the ground level for disassembly see Figure 15.
1 x 4 roof deck, top of chimney, transport materials to storage: The remaining amounts of the 1 x 4 roof deck removed from original roof. The top of the chimney was deconstructed. At this point all accumulated processed wood – wood that had been deconstructed, separated and denailed was transferred to storage.
Ceiling plaster and lathe, 2 x 4 rafters: The ceiling plaster was removed by standing on plywood deck on top of the ceiling joists and pushing down between joists with a sledgehammer. The remaining 2 x 4 rafters are removed.
Remove Kitchen addition to the floor deck: The house had an addition – the kitchen. This addition was removed from the main structure. The roof, ceiling, and walls of this area were removed.
Porch roof tin, asphalt shingles, mixed type wood roof deck, transport materials to storage: The metal rood on the West porch addition was removed. The remaining asphalt shingles were removed using a shingle shovels. The underlying 1 x 6’s and 1 x 3 roof deck was also removed. Again processed materials were transferred to storage.
No Work on Site
Porch rafters, 2 x 4 studs, 1 x 6 novelty siding: Deconstruction continued on the West Porch rafters and walls. Sections of the original exterior walls were laid down, the top plate and studs were recovered. Figure 16 shows an exterior wall being laid down for further deconstruction.
2 x 4 studs, porch rafters, 1 x 6 novelty siding, and front porch canopy: The porches are deconstructed down to floor deck. The attempt to deconstruct the front porch canopy as one unit results in the destruction of the salvageable material. Interior and exterior walls are taken down. Figure 17 shows studs being retrieved from the wall units once they are laid down.
Floor deck, 2 x 8 floor joists, foundation block and concrete: The floor deck of the porches is removed. This 1 x 3 decking material is easily removed. Unfortunately for het salvage effort, recent rains have caused the flooring to cup and pull up from the floor joists around the house. Although this resulted in ease of removal – the removal could take place without the use of tools, the material where exposed to the rain. Figure 18 shows flooring being removed to expose the floor joists.
2 x 4 studs, 2 x 4 ceiling joists: The crew focus was returned to the main structure. The ceiling of the original structure consisting of 2 x 4 rafters then 2 x 4 studs was removed. The original house is divided in four equal quadrants by the stud walls. The 2 x 4 ceiling joists were removed in one quadrant leaving the next to brace the exterior wall. The surrounding exterior stud wall was then cut free with a skill saw. This allowed the stud wall to be easily pushed over for deconstruction on the ground.
1 x 3 floor deck, 2 x 6 floor joists, 4 x 6 floor beams, transport materials to storage: The 1 x 3 floor deck of porch and support joists were removed. The brick foundation pillars are left in place. The exposed joists are then disassembled in Figure 19.
1 x 3 floor deck, 2 x 8 floor joists, 3 x 10 and 6 x 8 floor beams: The 1 x 3 floor deck of original structure is removed along with the floor support beams. The 1 x 3 decking appears to cup more when there is less resin in the wood. Approximately every other board of 1 x 3 is cupped due to water damage from the rain.
Due to nailing, the floor joist must be cut free for retrieval as shown in Figure 20. In this instance non-destructive removal could have been accomplished if the joists were bolted versus being nailed. If the structure was designed and constructed with the process of deconstruction in mind, the disassembly would be easily facilitated. Designing for disassembly would increase the speed and recovery rate of deconstruction projects.
Foundation and chimney brick, garage demolition, roof and walls: The remaining parts of the chimney were pushed over with 2 x 4’s, see Figure 21. As many bricks as possible were picked up from chimney and foundation. The remaining brick was left to the community to harvest. The tin of garage roof was blown out from underneath using 2 x 4’s. The 1 x 4 purlins and the 2 x 6’s were deconstructed. The garage doors were given away on the job site. At this point the final load at salvaged materials were taken to the storage facility.
In looking at Figure 21, it can be seen that the chimney is knocked down after the wooden material was recovered. It was noted during this process that bricks falling from the top of the chimney, a distance above 4 feet, had very little mortar remaining on them. The bricks closer to the ground require additional labor to remove the mortar (Figure 22).
Demo concrete, block, brick – After all remaining materials were salvaged, a demolition subcontractor was called in to crush the concrete block walls.
Demo final concrete pad, Recycle remaining metal – The concrete house pad was crushed for removal. All remaining metals were recycled. Unfortunately, during the evening of the 21st day, approximately 800 Lbs of sheet metal was stolen.
As a result of recovery projects across the nation, large quantities of lumber are reclaimed. Both small dimensional, Figures 23 and larger dimensional lumber Figure 24 can be reclaimed.
9.9 Dismantling techniques
One of the greatest barriers to deconstruction is the concept behind dismantling buildings that were not intended to be dismantled. The barrier exists of the structure – that was not assembled for removal, and the materials used in the structure that were not secured or constructed to be taken apart. For example in reinforced concrete structures where the joints are poured together. This manner of construction makes deconstruction extremely difficult. A possible disassembly technique would consist of sawing the structure to remove the joints. However, this method exposes steel reinforcing to the air, which causes iron oxide to form and the concrete to sprawl from the steel. The key is finding methods to disassemble the structures that do not damage the potentially reusable elements. Technical constraints have been designed into each structure simply because no architect or builder designs and constructs a structure thinking it is going to be removed. This brings up the point of designing for deconstruction. Further research is needed into this concept to determine the process needed to design for disassembly
Deconstruction is basically construction in reverse. It is important to take into consideration the potential for hazardous material and unknown building elements at they can contribute significantly to the cost of deconstruction. One of the best tools to determine a buildings deconstruction potential is a building assessment. This establishes what materials are believed exist in the structure and what potential recovery quantities exist. The building assessment is often followed by an environmental assessment to correctly identify and dispose of potentially hazardous materials. Preparing the jobsite and workers to ensure safety is then followed by the disassembly of the structure.
10.1 Establishing Deconstruction
SuPCCEssful establishment of deconstruction is a combination of coordination and dedication between several working groups. The groups include government, deconstructors, reusers and retailers.
Governmental agencies can work together with regional businesses to support the implementation of deconstruction.
- Pass ordinances requiring deconstruction to be considered in conjunction with or as a replacement for demolition through the use of building assessments.
- Inventory and assess abandoned buildings and those scheduled for removal to identify good candidates for deconstruction projects and make the database of information available to the public.
- Require redevelopment projects to review building components in structures scheduled for removal to assess their reuse potential.
- Use government contracting processes, such as Requests for Proposals (RFPs) by including materials recovery requirements, requiring salvage and reuse plan, and or awarding points in bidding process for high recovery rates.
- Tie approval of and fees for local demolition permits and environmental reviews to maximize materials recovery
- Covert HUD public housing demolition program funds to deconstruction program funds focusing on community enterprise development.
- Require a minimum content of used building materials in local government construction and renovation projects.
- Publicly acknowledge the training benefits associated with deconstruction and be willing to pay for them.
- Support used building materials yards and other end markets for materials salvaged through deconstruction
- Assist deconstruction service providers with resolution of issues surrounding lead paint and asbestos remediation
- Develop a network of deconstruction service providers and advocate who can work together to overcome local barriers to deconstruction.
- Require the complete removal of hazardous materials, and separate bids for this work, for all demolition and deconstruction projects, to level the playing field on this expensive issue
- When reviewing bids, allow a price preference for hitting deconstruction targets
- When possible separate the permitting, contracts and/or financing for site clearance from the design/build phase of construction projects to allow adequate time for deconstruction.
- Train license deconstruction firms to perform hazardous material abatement and or develop parallel specialized abatement enterprises.
- Deconstruction can be linked to concurrent construction projects to maximize efficiency.
Deconstruction is a worthy pursuit for community based organizations, government, and those seeking to develop public-private partnerships. It is especially relevant for the following organizations
- Housing authorities
- Redevelopment agencies
- Job training and employment agencies
- Community development corporations
- Local reuse authorities for closing military bases
- Low-income housing developers
- University research and business assistance programs.
In order for complete deconstruction to be suPCCEssful and profitable, there must be an outlet for the materials salvaged. Many materials can be directly reused, but a use for the non-sellable items is invaluable in keeping the materials from the landfills. An operation, which can make use of the smaller pieces of lumber and other materials considered scrap – such as furniture building, would not only provide an outlet for these materials, but provide an increased income from the value added products. The materials salvaged by deconstruction can be sold for reuse as-is or they can be remanufactured into new products. The most versatile and valuable of these materials is salvaged wood. Value-added wood reuse enterprises have the potential to create long term training and employment opportunities, since they can use feedstock from a variety of deconstruction projects. In turn, by developing a market for salvaged wood, these enterprises can make deconstruction more profitable, and therefore more competitive with demolition.
10.2 Deconstruction Process
- While deconstruction creates more jobs, it takes from two to ten times longer than traditional demolition. Planning as far in advance as possible to incorporate deconstruction is the best solution. The importance of proper planning can not be overemphasized.
- Containers, wood denailing and brick cleaning stations and materials storage should all be located carefully. These areas should be located to create a safe jobsite, minimize waiting time, and maintain aPCCEssibility to stored materials by hauling equipment.
- Flexibility is the key to job site efficiency. The supervisor should always be ready to move a denailing station, reassign workers, or change the size of a crew to accommodate the flow of materials.
- Taking the time to pull plaster directly into wheelbarrows was more efficient than pulling all the plaster to the floor and subsequently loading wheelbarrows. Pulling the plaster directly into wheelbarrows required approximately 27 percent less labor hours. Because plaster was applied over gypsum lath boards the plaster and lath could be pulled down in sections.
- Disassembly of framing on a flat deck was faster (and safer) than on a pitched roof section.
- For materials being hauled away during the deconstruction process (trash, inert rubble, etc.) a hauler providing timely service is critical. Considerable labor can be wasted reassigning workers or moving materials twice while waiting for a dumpster.
Manual disassembly of masonry walls requires more labor and yields a lower recovery rate than wood framed walls. Masonry consumed 41 percent of the total labor hours with relatively low percent recovery. By contrast, wood framing was easily taken apart with bars and hammers and with a high recovery rate of materials (NAHB, 1997).
Sheathing boards laid diagonally to joists are easier to remove than those laid perpendicular to joists. The 45-degree angle between the diagonal sheathing and hoists allowed a pry bar to hook under the sheathing board instead of being hammered under the sheathing board.
Generally clay tiles, and all natural slates are desirable for re-use, concrete tiles are usually crushed and screened to produce recycled aggregate.
Try to design roofs with safe aPCCEss, built in edge protection and anchor points. Using soft, non-ferrous fasteners prevent almost all the breakage occurring while stripping roof.
Findings – half of the labor for total deconstruction was spent on disassembly and half was spent on processing
Job training potential – manual disassembly of light frame buildings represents an excellent opportunity to identify and develop low skilled workers with an aptitude and interest in the building trades.
Diversion Rate – 70% by volume of all materials from the building were salvaged or recycled.
Salvage Value – Commodities such as framing lumber have wide application and are relatively easily sold for approximately 50% of their new retail value. More finished and use specific materials such as windows have a much lower proportion of retail value and require more intensive and targeted markets
10.4.1 Salvage Value
As materials are reclaimed, the deconstructor must determine the value of the materials. In general the materials can be placed in three categories.
- Materials whose value is a small fraction of their new counterpart (less than 25%). The low value of these materials is a function of their condition or their original value
- Materials whose value is a significant portion (50-85%) of their new counterpart. These materials can substitute one for one for readily available new counterparts. The previous use of these materials does not affect the way in which they can be reused.
- Materials whose value may equal or exceed (100&+) their new counterparts. The value of these materials has increased over time because:
A.) One or more of their qualities can no longer be obtained in readily available counterparts
B.) The qualities currently can only be obtained at a substantial premium
C.) The material can be processed or remilled to add significant value
10.4.2 Factors Affecting Salvage
Value Types of Materials – commodity materials such as framing lumber have wide applications, are used in large quantities, and so are relatively easy to sell. Finished materials such as windows and hardwood flooring have specific dimensions, specific uses, and require more targeted market.
Time of Year – depending on geographic location, construction firms may be more interested in building materials in non-winter months
Condition of local economy – demand for all building materials can be expected to be strong when construction and remodeling activity is strong.
Retail building material prices – the value of used building materials can be considered strictly a function of new building material prices. When lumber prices go up, any alternative to conventional retail becomes more attractive.
Condition – the presentation of well stacked, sorted, and labeled materials may attract more attention than those loosely piled.
10.4.3 Outlets for Materials
A determination must be made as to what will be done with the materials. The following outlet options are the most common.
- Materials that may be salvaged and immediately reused or slated for resale,
- Materials that are salvaged and will be donated (those materials with little or no resale value)
- Materials salvaged for recycling (this includes materials requiring further processing – i.e. not usable in their current form)
- Waste materials
10.4.4 Marketing approaches
There are several approaches to selling the salvaged products. The method used will depend on the quantity and quality of the materials available for resale and the location of the project. The most common methods are: 1. Direct market to retailer/end users; Broker; Auction; and Site sales.
The process of selling or brokering on a wholesale level. Prior to widespread use of reclaimed lumber in the California area, one of the most active markets for the reclaimed lumber industry was the wholesale selling and brokering of rough, unmilled timbers and lumber. The network is one of the best way to move large quantities of material quickly, however this option will not prove as profitable as selling retail and in smaller quantitie
Products may also be sold in a retail fashion. As with the sale of rough wholesale lumber, the primary benefit sought by customers is a low price for good quality. Unlike the wholesale market however, new lumber is often the direct competition. The price must be low enough to compensate for the lack of other benefits. Buyers tend to look for a sense of history, uniqueness and adventure in the purchase of this reclaimed lumber.
Often individuals seeking low cost materials will visit the deconstruction site while the project is underway expressing their interest in the materials. It was also noted that selling materials on site provides the workers with a greater sense of accomplishment. The workers can see the materials they labored to save in demand.
Designing for Deconstruction
With existing buildings containing so many useful materials it is important that these materials be aPCCEssible for reuse after the building has exceeded its service life. When considering buildings as a future source of raw materials designing for disassembly is a key element in material retrievability. Additional issues are material durability, desirability and longevity. Materials must be durable if they are to be used over several service lives.
By definition deconstruction is an age-old concept of reusing existing structures to create new facilities. However, designing for deconstruction from a practical standpoint is a difficult concept to grasp. Designers conceptualize their buildings as being timeless, no designer intends on spending intensive labor creating a building only to be torn down. The designer’s perception is that the building will stand forever. Similarly, no contractor believes that their structure will be torn down. Designing and building structures to be taken apart goes against these professionals’ principals. The concern of marketability is always in the forefront of construction. Many products today are not produced with recycling in mind but rather the selling cost. Manufacturers today focus on generating the least expensive product for the short term. A return to traditional materials and methods means incorporating products and building techniques, which have stood the test of time and are still preferred by home buyers. For example, if a vinyl window is specified, at the time of deconstruction will the window be worth reusing or recycling? Many technological advances in materials – for example, composites – make dismantling extremely difficult. Solid , durable, high quality materials are preferred from a deconstruction standpoint.
As people age, they tend to move through a well-defined housing consumption cycle: from renters (ages 20-24), to first-time homebuyers (ages 25-34), to trade-up buyers (ages 35-54), and then to long-term owner or retirement homebuyer (ages 55 and over). Over 3 million homes change ownership annually. This, coupled with an aging housing stock, assures the remodeling industry growth for decades to come. Few other markets can compare with this kind of growth. There are a total of 115.6 million housing units in the US; 102.2 million are occupied, 67 million are occupied by owners, 35 million by renters
Design for Disassembly has been used most frequently in Europe in response to Extended Producer Responsibility laws that require companies to take back and recycle their products. The automotive industry pioneered techniques for disassembly that the construction industry employs. There are currently no such EPR laws in the United States, but private industry may be forced to change its practices, as landfills overflow, and tipping fees rise.
For an example of potential design changes that could facilitate disassembly, a local builder was interviewed regarding designing for disassembly.
11.1 Dibros Corporation
To look at designing for deconstruction on a practical level, view deconstruction from the viewpoint of a builder using traditional concepts. Dibros principals Miguel Diaz and his son Luis A. Diaz are among many builders in the Gainesville location. Dibros, in order to make their development more attractive to potential homebuilders, has committed to developing a “neighborhood”, using the concepts of New Urbanism. New Urbanism also stresses “traffic calming” through street design and takes the focus away from the automobile and puts the focus on the people. This concept also mixes retail and light commercial businesses with housing.
Dibros began planning their community as most builders do, by taking a survey of the land, and planning roads and lots accordingly. However, Luis Diaz, decided that instead of having the design dictate the acreage, he would let the land dictate the design. They created a Computer Aided Drafting (CAD) plan of the land marking trees, which ultimately determined the layout of roads, lots and common parks. This community, from the start, was developed in a non-traditional manner. After speaking with Luis, it became evident that he was interested in new, innovative, environmentally friendly construction materials as well innovative construction techniques.
11.2 Components of a Dibros Home
For the purposes of deconstruction, it is important to look at the typical components of a home built by Dibros. Listed in Table 11 are the highest cost items in the Dibros home.
After reviewing this list for items which warranted further research we eliminated items such as paint and stucco which from a deconstruction standpoint have little value.
Further investigation of these components shows the highest cost item, Roof and Floor trusses to be the most expensive item. The trusses are constructed of engineered wood in Melborne Florida. The builder agrees purchasing from a local producer would be less costly, however, Space Coast Truss provides them with excellent quality control. Lumber is the next highest cost category. These components will be further investigated to determine the feasibility of reuse or recommendations for an alternative material. Components investigated are the most costly items used in the construction of the Dibros home.
11.3 Foundation systems and Flooring
The foundation system is a concrete slab and for the house that was examined the finished floor was Hartco wood flooring.
Hartco Flooring is a 3/8” glue down laminate wood flooring with true wood layers. Deconstruction alternatives are listed below. It may be noted that flooring and floor covering are subject to physical abuse from feet and heavy objects, and as the lowest spot in a room they tend to collect dirt, moisture, and other contaminants. A good flooring material should be highly durable to reduce the frequency with which it must be replaced, and it should be easy to clean. At the same time, softer surfaces may be preferred for reasons of comfort, noise absorption, and style, setting up a potential conflict for the designer. There are also raw material and manufacturing impacts to be considered with many types of carpeting and other floor coverings.
11.3.1 Concrete Slab
The aPCCEptance of concrete slabs comes from a purely marketability standpoint. A concrete slab takes less time and cost to install. After the service life of the home, the concrete slabs may be reprocessed. The broken concrete is sent to a manufacturer who can incorporate crushed concrete (used as aggregate) back into the concrete manufacturing process. The crushed concrete is most often not immediately reused, one exception is where they crush the concrete on site and use it as a temporary road base.
In the process of recycling concrete slabs the question remains as to the total aPCCEptance of recycling the wire mesh, vapor barrier and gravel as part of the system or as a separate commodity. The alternative methods of covering the slab need to be addressed as to their deconstructibility.
- The EPA has identified carpet systems as a potential source of indoor air pollution, including carpet pads and carpet adhesive. Although carpet recycling is technologically difficult, due to the contaminants and multiple components of used carpet, some companies now have extensive recycling programs. Carpet padding has long been made of recycled materials and is extremely recyclable. One problem with carpet is that it will hold in dirt and pesticides creating a unhealthy environment. Life expectancy of carpet on slab is reduced due to the harsh backing concrete offers.
- The thin wood-flooring composite is glued down. Any attempt to remove will lessen the quality of the material making it less desirable for reuse. It is essential to ensure the adhesive is not toxic or in any way harmful to the environment for disposal purposes. Further, these products do not take excessive abuse and will not allow numerous resurfacings.
- Ceramic and Porcelain tile have a high-embodied energy but their durability makes them environmentally sound in the long run. Some high quality ceramic tile incorporate recycled glass form automobile windshields. As a floor or wall covering tile is durable and recyclable.
- Linoleum has no reuse associated with it and does have any recycled content.
Concrete is less forgiving to both the human body and the materials that cover the slab. Concrete slabs provide other problems; cracking form settling and major renovation to repair utilities under the slab.
11.3.2 Crawl Space
In comparison to the slab on grade the crawl space provides many incentives. The marketability view is the prestige and elegance associated with it not to mention its durability. The time and cost are higher but it may provide less maintenance concerns than a concrete slab. Of primary interest for deconstructability, is the immediate removal and reuse of all components in another facility after re-certification. The alternatives for coverings provide the same description for reuse and recycling as above except the following:
- The wood flooring is a return to traditional tongue and groove wood that has always stood the test of time. It does not require excessive resurfacing, provides a cleaner surface and is more forgiving to the human body and other materials. The quality of floor temperature is easier to control.
- Area rugs can be incorporated which protect the wood and provide a more favorable environment. Wall-to-wall carpeting can be used with an extended life expectancy.
Crawl spaces provide easier and cleaner coordination of utilities, not to mention easier aPCCEss for maintenance. The space can also be incorporated into a passive cooling system throughout the facility reducing consumed energy.
Dibros currently uses southern yellow pine framing. The debate over wood versus steel in structures is not only a long debate, but depending on your personal preference can benefit either side. There is a strong push for both materials depending on if you represent the steel industry or wood producers. From a deconstruction standpoint wood and steel both have advantages and disadvantages.
Wood is a renewable resource, if it is purchased from a sustainably managed forest. This is more difficult than it may initially appear. The process of following the lumber from forest to mill to manufacturer is not easy and is costly. For this reason, the purchasing wood, even if it is marked as coming from a sustainable forest, should be taken with a grain of salt. It should be noted that it takes approximately 40 – 50 trees to construct a 2000 sf home (E Build, 1997). From a deconstruction standpoint however there is a potential to immediately reuse some of the wood salvaged from the site. The wood that cannot be immediately reused may be recycled. With increasing technology, less and less of the tree will be left for scrap.
Although steel is a finite resource, steel is the most recycled material in North America. Steel framing members contain at least 28% recycled content and generate as little as one cubic yard of recyclable scrap (Steel Recycling Institute, 1999). Steel framing requires approximately 30% more labor to construct than a typical wood framed homes. Unfortunately to immediately reuse steel framing members, they must be deconstructed with great care to avoid warping, twisting, or bending during disassembly. Even though the steel may not be available for immediate reuse, all of the steel may be recycled.
11.5 Wall Finishes
Dibros currently uses gypsum drywall in ½” X 4 X 12 sheets with a texture finish veneer plaster.
A disadvantage of drywall is the large amount of waste generated during construction. Drywall generates about 15% of all construction waste and represents the highest percentage by weight of waste in residential construction. For a typical 2000 square feet home, 2000 pounds or five cubic yards of waste is generated (Smart Growth Network, 1998). This equates to one pound of waste per square foot of building. Recycled gypsum drywall is available and is becoming more prevalent in the US Specific types of drywall for fire rating and moisture resistance contain products, which cannot infect the recycling system. In addition to the large quantities of waste created from the construction process drywall has little to no value with respect to material recovery. The drywall acts as more of a barrier to the materials that deconstructors are trying to retrieve.
Dibros currently uses asphalt-roofing shingles. Roofing provides one of the most fundamental functions of the building, shelter. Roofs must endure drastic temperature swings, long-term exposure to ultraviolet light, high winds, and extreme precipitation. Durability is critical in roofing because a failure can mean serious damage not just to the roofing itself, but also to the entire roofing system, building and its contents. Such damage multiplies the economic and environmental cost of less reliable roofing materials. Roofing can also have a significant impact on cooling loads. Use of lighter colored, low-solar absorbency roofing surfaces is one of the key measures in life cycle energy costing associated with a home. All roofing options do not allow for immediate reuse however comparisons of the various options are listed below.
Asphalt roofing is the most affordable up front option for roofing, however its service life can range from 10-30 years depending upon the grade of tile purchased. As far as deconstruction is concerned, the tile may not be immediately reused nor is it readily recycled. Manufacturers publicize the recycling of asphalt roofing in road mix designs, however, the FDOT uses no asphalt roofing in their paving operations. Research is being conducted to incorporate asphalt roofing into mix designs, however the roofing the FDOT is using is waste from the manufacturing process, not waste from the roofs of homes. The FDOT reports there is simply too much contamination and inconsistency in the “take-offs” to use this waste when trying to create a predictable mix design.
Options for metal roofing include galvanized steel, aluminum, and copper. Metal roofing is a great alternative to the common problems experienced with traditional roofing shingles. Metal roofing does cost more up front than a typical shingle or tile roof, but it is actually cheaper because of its longer service life, (approximately 3 times that of a shingle roof). In addition to the longer service life, metal roofs have fewer maintenance requirements, provide a better appearance, and greater value for homes (Morrison County Record, 1998). Because of the low maintenance and long life, steel-roofing systems can ultimately be one of the lowest cost roofing materials (Weirton Steel Corporation, 1997). The benefit related to deconstructability of metal roofs is the well-established metal scrap market. Even regions of the US where there is no deconstruction infrastructure there will often be metal scrap dealers. Aluminum is also one of the most valuable materials to recycle.
Wood shingles, although may not be immediately reused, may be readily recycled. The expected life of a wood shingle roof however, is only 15-20 years. Code requires that wood shingles carry a specific fire rating which affects their make up and recyclability.
There are a variety of new products on the market made from recycled polymers. One product is made from asphalt and recycled baby diapers, which has the appearance of slate and includes a 50-year warranty. With this composite type material reuse or re-recycling this product will be difficult.
11.6.5 Tile / Concrete
Clay and concrete tiles are also an option where hail is not a serious threat. Both of these roofing options offer excellent service lives, however may not be locally available. Local availability of these products is an issue due to their weight that would result in high transportation cost. Tile and concrete roof tiles can be deconstructed and the material can be crushed and used in new concrete as aggregate or as road base.
Slate is one of the most durable roofing options with an expected life span of over 100 years. This roofing material is also very expensive yet desirable. Slate is reusable if it is not cracked. Pre manufactured nail holes reduce the amount of waste created.
Dibros currently uses a combination of Hardiplank, and concrete stone depending upon the customers specifications.
Today’s vinyl siding provides a 20 year warranty because of its innate durability and flexibility. It is installed with nails or other fasteners that increase the labor associated with deconstruction. Vinyl offers low maintenance, it does not need to be painted or stained. However its recyclability is questionable since heating of vinyl produces hydrochloric acid (HCl). Recycling of vinyl results in downcycling, meaning that existing vinyl siding will not be recycled into vinyl siding again, but a product lower on the product cycle chain.
Wood is a traditional material, just like brick, but unlike brick, it will require more maintenance and has a shorter life. Life expectancy is shorter because of the possibility of termites and weathering. In addition, wood requires continuous upkeep, maintenance, and painting. If wood is properly maintained it may be removed and reused. Removal would be easily facilitated with the use of screws versus nails.
Hardiplank™ is an extremely durable composite made of portland cement, ground sand and cellulose wood fiber. This product offers a 50-year warranty and is resistant to humidity, rain, and termites. Hardiplank™ is potentially 100% recyclable, however, there is no current recycling process in place. Figure 4 shows a typical home sided with Hardiplank™.
Brick offers the best immediate re-use potential. Locally produced brick and stone are long lasting, low maintenance finishes that reduce transportation costs and environmental impacts. Molded cementitious stone replaces the environmental impact of quarrying and transport of natural stone with the impacts of producing cement. A summary of material and labor cost associated with the preceding siding option is listed below.
11.8 Design for Deconstruction – Recommendations
There are five design elements to reduce generation of C&D waste
- Reuse existing buildings and materials – It is possible for new buildings to be designed to facilitate the reuse of existing materials from existing structures
- Design for durability, Design for adaptability – Longevity is determined by durability of materials, construction and by the buildings adaptability to changing needs. Durability needs to be properly balanced with adaptability. Different material life spans must be factored into design.
- Design for disassembly
- Use less material to realize the design
Deconstruction as an alternative to demolition can provide many environmental, economic and social benefits. Deconstruction has the potential to divert a significant portion of the demolition and renovation waste from landfills. This process requires an infrastructure of businesses to support the flow of materials and workers to complete the deconstruction process. Unfortunately these two key components are not abundant. Additional barriers to establishing deconstruction include the cost and industry attitude. The primary concern of business is to make a profit.
Without regulations, industry will simply continue to operate business as usual, offsetting increasing disposal costs by charging more for disposal services. Although deconstruction case studies have shown that there is a profit to be made, the underlying truth is that deconstruction to the demolition contractor – in most parts of the country – does cost more than pure demolition. In order to realize a profit – or get the costs in the same ballpark as demolition, the resale of salvaged materials must be factored in. Most demolition contractors are not in the raw materials sales business and as such see no benefit from deconstruction. In addition demolition is usually conducted under a tight schedule – the allowance for the extra time needed to deconstruct is simply non-existent. In addition to time constraints, the hazardous material exposure potential – i.e. purchasing the appropriate equipment per OSHA and EPA standards is simply cost prohibitive for most demolition contractors.
Many factors influence the cost of deconstruction. The most dominant cost for this process are driven by regional factors. For the Southeast, tipping fees are low and the building stock is young which works against implementation of deconstruction. In addition, areas with established outlets for the used building materials are sporadic at best. The importance of used building materials stores and consumers cannot be overlooked. One great benefit to the South is that labor costs are low. When considering the labor-intensive nature of deconstruction, this works in the favor of implementation. However labor costs cannot work alone. Regions that are currently not favorable to deconstruction will experience growth, rising tipping fees and aging building stock, all factors that prove favorable to deconstruction. Without a significant rise in tipping fees, it is simply too easy for contractors in the State to continue landfilling items. For deconstruction to work, tipping fees must rise.
Putting all other benefits aside such as environmental benefits, waste reduction etc., the bottom line in business operation is that cost is the driving factor. Businesses simply look at a cost per square foot to perform the job in the simplest manner and the fastest way to make the most money. The positive costs resulting from deconstruction cannot be easily quantified. The difficulty arises from placing a price on the environment. The difference between man-hours needed to demolish versus man/hours needed to deconstruct can easily be calculated and quantified. However, most businesses ignore true full cost accounting that includes environmental preservation versus degradation.
The harder to quantify items such as environmental benefits, job creation and economic development can be considered priceless in some regions. The location of the deconstruction operation is one of the most important factors in the suPCCEss of the operation.
The implementation of deconstruction requires not only a change in traditional material flow, but also a change in mindset. Instead of considering used building materials a waste product they should be considered simply raw materials. Instead of these valuable and usable materials being landfilled the materials can result in the creation of businesses to sell, supply or manufacturers new products from the materials.
The focus must turn to thinking of a building as an integrated system. Environmentally responsible building design covers a broad range of considerations, some of which are difficult to quantify. It is necessary to judge overall building performance and cost effectiveness while linking them with environmental issues and design considerations. Industry is faced with needed environmental information not being equally aPCCEssible to all , the owners, designers, builders, and users.
Increasing awareness of the importance of natural resource depletion and environmental degradation influence long-term economic growth (DAAE University of Wisconsin-Madison, 1998). The main problem we face as a society is attitudes against change. It is ultimately the general public who will demand and drive change in the construction industry. By informing the public and owners in general, they will ultimately drive the market, which will force an industry change. The public also has the power to drive policy toward further environmental preservation.
Past environmental problems have been highly visible and politically charged. Protection of the environment has been a result of remediation, stopping the problem after it has done damage. Environmental degradation is not the problem but a symptom of an attitudinal and value system premised on consumerism and excess. The environmental crisis is a human problem and the solution depends on major changes in human values and actions. Environmental degradation is derived from a combination of conscious choices made within a societal context, which has different priorities and ignores the environmental effects of design decisions. Even with the current cost and regulatory constraints, architects and builders can design more environmentally responsively and responsibly. However, it is still necessary to consider different design priorities. The attitudes, commitment, and priorities of the design team will ultimately dictate the rate of progress in environmentally responsible building design and construction.
There is an obvious environmental hierarchy when it comes to the deconstructing of structures. First, we want to immediately reuse any building components possible. This has the highest priority from an environmental point of view because all resources (material and energy) put into the product during manufacturing are preserved. This often provides economic advantages as well. The negative aspect of deconstruction for reuse is that it requires non-destructive disassembly and additional inspection operations that may increase cost (Dismantling and Recycling Strategies, 1999). Material recycling is the next best action. It is important to rethink the practices that have generated waste and to develop new means of diverting construction materials from the traditional waste stream.
Several areas are in need of additional work to promote and establish deconstruction.
- Information needs to be transferred from the research entities to the industry for implementation.
Research entities have the ability to completely evaluate, analyze and understand complex issues. However, these entities have very little actual influence on the daily operations of the regions. It is necessary to bridge the gap between the pure research and application of the knowledge by informing governments and industry as to the research finding for implementation. The government entities an industry have the power to promote change and as such must be well informed.
- Government involvement in the incentive process for deconstruction is needed to promote the concept and assist in development of the needed infrastructure.
A key driving factor remains cost of deconstruction. Industry and communities need government intervention in the for of incentives such as subsidies for deconstructing or starting resale businesses, or disincentives in the form of increased tipping fees to push the use of alternative disposal techniques.
- Further evaluation is needed within the State of Florida to determine if the State waste percentages actually mimic the EPA waste stream.
It is expected that since Florida is growing at a much higher rate that the waste stream may not follow the National Average. A complete review of the actual Florida waste stream is needed to determine specific actions for the State.
- Additional research is needed to completely understand the effects of age and nail holes on lumber.
This information will assist in the establishing of regarding guidelines.
- The cost of disposal should accurately reflect the complete costs associated with the process.
This includes a full cost accounting, including necessary environmental issues of both the materials and landfilling operation. Consider penalties associated with discarding potentially usable materials.
- The process of deconstruction should be assumed from the conception of a structure.
It is essential to acknowledge the actual life span of most structures and design accordingly. Designing for deconstruction is a key element in the process of sustainability.
- Use screws versus nails
- Label materials
- Use less materials
- Change disposal frame of mind
- Share industry information
- Buildings of today should be looked at as future resources of building materials.
For New Construction
- Examine Design process (design for deconstruction)
- Design for recycling
- Acknowledge structure life span
- Link design with eventual demolition
- Technology transfer for new building materials and systems to industry
- Recyclability of building elements
- Provide appropriate guidelines to architects, using previously stated information
- Rating system for construction materials, based on their “greenness” or reusability/deconstructability