Analysis & Building Placement

Any site analysis should begin with the identification of the prominent features such as existing vegetation and topography. Preservation of the sites natural features can result in cost savings associated with:

  • Reduced landscaping cost
  • Energy conservation from shading
  • Reduced water use (Xeriscaping)

-Woods, woodlands lakes trails and streams are important amenities that should be preserved. Protecting these features when building can result in higher property values. (ALS)

Reduce Environmental Impact of Site Location:

-Selecting sites in developed areas 
-Selecting sites that do not contain or encroach upon sensitive environmental features
such as wetlands 
 
-Consider factors such as thoroughfares, infrastructure, existing structures, zoning of adjacent parcels and the characteristics of the surrounding communities  
-Selecting sites close to public transportation, amenities, and places of employment to minimize the impact of vehicles.  
-Ideal site would provide clean air, water, soil, solar aPCCEss, have public transportation, be close to amenities, utilize existing roads and utilities and have the potential to be developed without causing environmental damage  
-Select a site that allows use of passive design, such as building orientation (allow the longer sides of the house to north or south) and good shading 

Site Analysis Checklist

– What features exist on site? 
– How might a development be oriented to best preserve natural features? 
-Is there possible restoration of existing ecosystems? 
-What are the characteristics of trees located on site, location, age, and species? 
-One effective way to do a site survey is to take a topographic map or survey of the
site into the field and make notes directly on it. (ALS)
 

Building Placement & Orientation

Where the building is placed can have a great influence on the effectiveness of passive design strategies, particularly as they relate to solar radiation and wind. In southern climates such as Florida, buildings should be oriented to minimize the sun’s radiation on the structure and to maximize the potential for cooling breezes. Effective passive design is possible, however, compromises are often required regarding sun and wind orientation strategies. In low structures such as homes, wind orientation is not as important as avoiding solar radiation. Air flow through a building is more dependant upon the use of windbreaks, and the proper location of window and door openings than the buildings orientation.

All buildings, no matter what climate, perform better if the longest wall faces the south. The optimum shape of a Florida home is rectangular, elongated on its east-west axis at a ratio of 1:1.7 in order to maximize its north and south surface area, therefore minimizing east-west’s exposure to solar heat gain.

The rule for ventilation with regards to building orientation is that air flow is often better captured when the house is placed off the cardinal (north-south) directions by approximately 30 degrees.

Important Natural Features Determining Building Placement:

  • Topography
  • Wind
  • Sun
  • Water
  • Habitat
  • Landscaping

Properly designed landscaping can:

  • Prevent water runoff
  • Reduce solar gain
  • Reduce energy consumption by 30 percent
  • Reduce air-conditioning consumption by 75 percent
  • Reduce water consumption by 80 percent.
  • Control pests without chemicals and invite wildlife [15].

Practices for Green landscaping:

  • Preserve existing vegetation and native plants.
  • Protecting existing plants during construction.
  • Using primarily native plants for new landscaping, as they require less water and
  • maintenance than exotic plants, and reserving exotic plants for aPCCEnting.
  • Using plants that will attract wildlife.
  • Using organic mulch around plants to conserve water and maintain favorable soil
  • temperature
  • Avoiding use of exotic species that will overrun native plant communities
  • Avoiding plants of all one species or age and plant diverse communities of species.
  • Avoiding the use of conventional grass lawns and typical ornamental shrubs due to
  • their high water use, pesticide use, and the pollution generated from mowing.

Benefits of trees include:

  • Shielding the house from noise.
  • Reducing the energy consumption of the house by shading the house from sunshine during hot summer months.
  • Cooling, humidifying and filtering the air.
  • Proving an attractive and relaxing backyard area.
  • Minimizing the need for lawns.
  • Boosting the value of a home or lot. National polls have indicated that trees can increase the value of a home by up to 15%.
  • Saving money on landscaping after the home is built. (Source EBN Jul/Aug ’92)

Tree type and vegetation placement:

Palm trees are good choices for landscaping next to building, because their canopy provides shade but they do not block the natural airflow near the ground.

Trees can also be planted to either create windbreaks or to channel the wind into a building. Windbreak plantings diminish wind within a distance three times their height. Vegetation can be a valuable tool used to direct and aPCCElerate natural breezes into a
buildings interior.

Effects of a vegetationless landscape on the natural ventilation of a residence.

Effects of medium to high hedges in aiding to direct breezes through a home.


Stormwater Management

Responsible management of storm water is not expensive. Some of the following recommendations, taken from Environmental Building News, are actually less expensive than conventional modern stormwater management practices, especially in large
scale projects. Conventional methods include the use of culverts, rip-rap-lined channels, stormwater sewers and retention ponds. The following suggestions are based on designing projects to minimize the quantity of runoff generated and to provide
natural infiltration.

Strategies to Reduce Run-off

Minimize the impact of development by preserving existing landforms,
topography and vegetation and minimizing the creation of impervious surfaces
when possible.

Don’t let impervious areas connect to one another, so that one surface drains onto
another, it just compounds the problem. For example, don’t let a sidewalk drain onto
a paved street, separate them with areas of turf or vegetation. Do not install gutters unless collecting rainwater for use. Install gravel filled “Dutch drains” at the base of the wall instead. If using gutters, then install as many downspout as possible in order to disperse the flow over a wider area. Special gutters that disperse water outward away from the building are also available. In multi unit developments, reduce paved areas by clustering units, building narrower streets and providing off street parking on pervious surfaces. Consider using porous materials such as sand, shells, rocks or wood chips for walks and driveways to allow stormwater infiltration. Other pervious paving surfaces include porous asphalt and concrete systems, and module concrete or plastic grid pavers or block lattices that can be planted with grass. Construct porous paving systems over properly sized gravel reservoirs in order to combine parking and a retention basin within a single area. Eliminate curbs along driveways and streets if possible, so that water can run directly into grass or landscaped areas and does not become concentrated. Plant trees, shrubs and groundcovers to encourage infiltration. Incorporate native or low maintenance landscaping that does not require frequent fertilizer, pesticide and herbicide applications, in order to keep pollutants out of stormwater.