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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:
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| -Selecting
sites in developed areas
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-Selecting sites that do not contain or encroach upon
sensitive environmental features
such as wetlands
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| -Consider
factors such as thoroughfares, infrastructure, existing
structures, zoning of adjacent parcels and the
characteristics of the surrounding communities
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-Selecting
sites close to public transportation, amenities,
and places of employment to minimize the impact
of vehicles.
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| -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
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| -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
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Site
Analysis Checklist
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- What features exist on site?
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- How might a development be oriented to best preserve
natural features?
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-Is
there possible restoration of existing ecosystems?
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-What
are the characteristics of trees located on site,
location, age, and species?
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-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)
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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.
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