Site Selection Criteria – 12 Important Factors for Green Buildings

The Site on which we build can influence each and every aspect of the building we choose. In this article, you can learn about various aspects to consider in site selection.

The primary goals for green buildings in selecting a site are

• Protecting sensitive sites
• Preserving undeveloped sites
• Restoring and Reusing previously developed sites
• Reducing impact on flora and fauna
• Promoting connection to the community
• Minimizing transportation impacts both the environment and energy use.

1. Site Selection Criteria

• The site selection and site plan must fulfill the regulations and guidelines of UDPFI, Eco-sensitive zone regulations, Coastal zone regulations, and any other specific local bye-laws.
• Minimizing land disturbances by selecting previously disturbed lands; sites that are close to public transportation, community and work centers, and services such as pumping water and transporting electricity.
• Minimize long-term impacts on the community.
• Creating neighborhoods with compactness, connectivity, and walkable streets.
• Climate zones (cold /hot/mixed) and Local Hydrology will have an impact on building design. The same type of building will be designed in a different way depending on outdoor temperature, outdoor humidity, and solar radiation. The design varies in various aspects such as:
  • Wall materials and assembly
  • Size and orientation of windows
  • Heating system selection
  • Methods for controlling moisture
  • Type of vegetation available for landscaping.
• Encouraging the use of less polluting modes of transportation.

2. Protection of Sensitive sites – Site Selection

• Site selection and protection of sensitive sites. These include
  • Prime farmland
  • Parkland
  • Flood hazard areas
  • Habitat for endangered or threatened species
  • Primary dunes
  • Old-growth forests
  • Wetlands and other water bodies (50′-100′ buffer space)
  • Conservation areas

• Not developing or undergoing any construction activities within these sites and also including buffer zones surrounding them.

3. Preservation and Restoration

• Greenfields are defined as previously undeveloped sites.
• Brownfields are abandoned industrial and commercial sites that have perceived levels of contamination.
• Greyfields are previously developed sites that are not contaminated and have a visible development and infrastructure
• Restoring and Reusing Brownfields to prevent/limit the development of Greenfields.
• Developing Greyfield and promoting urban density

4. Protection of Natural Features

• Minimize Site disturbance.
• Protecting the Site’s soil conditions.
  • Retaining soils in place.
  • Stockpiling and reusing soils.
  • Restoring soils during construction.
  • Revegetation of disturbed soils.
  • Measures to prevent soil runoff during construction.
• Protection of vegetation present on site.

5. Heat Island Reduction

The heat Islands are generated by the raised levels of temperatures from hardscapes and buildings, particularly in urban areas.

It refers to the absorption and retention of incoming solar radiation by the buildings and hard pavements surrounding them. When this heat is released into the atmosphere, heat islands are formed having higher temperatures in urban areas, compared to rural areas.

Effects of Higher Temperatures/heat Islands:

• Increased energy consumption for cooling during summers.
• Elevate emissions of air pollutants and greenhouse gases.
• Contribute to heat exhaustion.
• Heat-related Mortality.
• Stressing aquatic ecosystems due to raised temperatures of water in streams, lakes and ponds, rivers, etc.

Ways to Reduce the Heat Island Effect:

• Using light-colored roofing having high solar reflectance.
• Installing green roofs/Vegetated roofs.
• Including pavement with non-heat-absorbing materials.
• Planting trees
• Providing landscapes
• Shade Parking surfaces.

6. Site Waste Management

Manage the waste generated during site construction. It includes:

• Debris such as
  • Rocks
  • Soil
  • Vegetation
• Any other hazardous materials present

Strategies Include

• Prevent debris from moving to landfills.
• Restrict debris transported to sensitive sites such as wetlands.
• Reusing materials onsite itself.
• Recycling debris offsite.

7. Greener Forms of Transportation

One of the factors in the site selection process is transportation, proximity, and other facilities.

• Proximity to public transportation.
• Onsite Traffic Signs.
• Providing facilities of transportation that emit fewer carbon emissions.
  • Installing Bicycle racks.
  • Facilities for storing and covering bicycles.
  • Providing pedestrian paths.
  • Sidewalks for walking and biking.
• Vehicles serving Carpools.
• Encouraging Electric vehicles and providing electric charging stations.

8. Minimizing Light Pollution

Light pollution is the presence of artificial light in the outdoor environment.

Impacts of Light Pollution:

• Disrupts the habitat of nocturnal wildlife.
• Interferes with normal plant growth cycles.
• Conceal the night sky; interferes with the ability to view the night sky, stars, and planets.
• Causes light trespass – Spill of light into neighboring properties.
• Safety Hazard – Produces glare while driving.
• Assists Intruders – Increase security risks.
• Wastes energy – impacts environmental and economic concerns.

Strategies to Reduce Light Pollution:

• Select light fixtures that minimize spillage, and focus light downward rather than upward.
• Providing accent lighting for pathways instead of higher pole-mounted lighting.
• Eliminating Uplighting.
• Installing fixtures downwards.
• Locating outdoor amenities close to the main building.
• Motion sensors and time schedules keep exterior lights on most of the time.
• Eliminating exterior lighting wherever possible.
• Reducing lighting near windows.

9. Site Strategies and Energy Use in Site Selection

• A building on an exposed hilltop utilizes more energy than a building surrounded by trees or adjacent buildings.
• Trees, structures, fencing, and other forms of shielding help reduce wind velocity downwind of the barriers.
• Site planning not only refers to landscaping and natural features, but also exterior equipment such as air-conditioning condensers, cooling towers, and pad-mounted transformers.
  • Unlike buildings, this equipment operates more efficiently when not blocked by vegetation or structures.
• Energy use rises by 20% or more due to various risks such as
  • Air blockage by vegetation or other obstructions.
  • Contamination of heat exchangers by dust or pollen
  • Recirculation of exhausted air.
• Locating an outdoor unit in an enclosed or partially enclosed location will cause air recirculation and its high energy use.

Ways to reduce Increased Energy Use :

• Maintaining clearance between the units and buildings or vegetation.
• Locating units where outgoing air does not recirculate back into the units.

10. Storm and Site Water Conservation

• One of the important goals of green projects is to mitigate the negative environmental effects of stormwater runoff and reduce the use of outdoor use of potable water on the site.
• Impervious surfaces, buildings, and conventional storm drainage systems prevent rainwater from percolating into the soil.
• Surface runoff (also known as overland flow) is the flow of water occurring on the ground surface when excess rainwater, stormwater, meltwater, or other sources, can no longer sufficiently rapidly infiltrate the soil. (Wikipedia)

Effects of Storm Water Runoff:

• Soil erosion
• Habitat damage
• Flooding
• Water Pollution
• Groundwater Aquifer depletion
• Physical and chemical depletion of water resources.
• Transfers surface contaminants along the same path.

Strategies to Reduce Storm Water Runoff:

Quantity of Storm Water Runoff:

• Reducing hardscapes for parking.
• Minimizing on-site parking by encouraging public and non-motor vehicle transportation.
• Providing on-site percolation facilities.
• Replacing Impervious surfaces with permeable methods such as
  • Pervious pavers,
  • Porous asphalt,
  • Pervious concrete
  • Vegetated Landscapes
• Rainwater harvesting methods on site.
• Reuse of stormwater for landscapes and flushing toilets.

Quality of Storm Water Runoff:

Advantages:

• Improved on-site water quality.
• Improves water quality in downstream rivers and lakes, etc.
  • Thereby benefiting flora and fauna

Strategies to improve Quality of Storm Water Runoff

• Proper management of water quantity and its velocity.
  • Reduces containments, such as pesticides, biological waste, garbage, and sediments.
• Integrate pest management to minimize the use of pesticides.
• Minimize on-site vehicles and contaminants to them such as oil, grease, dirt, etc., carried by tires.
• Reduce onsite sources of pollutants – including pesticides, fertilizers, animal waste, finishes for outdoor structures, etc.
• Minimize artificial landscaping that requires chemicals.

11. Transported Water

Water is supplied by a municipal water system or well water that is sourced from an underground aquifer and treated on-site.

Impacts of Using Transported Water:

• Depletion of Potable Water Resources.
• Use of water treatment chemicals.
• Energy use and Power requirements for pumps.
• Excess and unnecessary use of water increases surface runoff.

Strategies to Reduce Using Transported Water:

• Employing water Efficiency measures.
• Using non-potable water wherever possible such as for landscaping, flushing, etc.
• Landscaping with native plant species that require fewer water resources.
• Installing efficient irrigation methods such as Drip irrigation.
• Selecting smaller fountains with fewer surface areas and with low flow rates.
• Metering of water use helps to monitor the usage of water.

12. Other Site Issues

Trees and vegetation, which are helpful for shading and protection from the energy effects of the Sun, can also adversely contribute to humidity and other environmental problems if located adjacent to buildings.

Trees can also threaten a building’s structure with their roots and branches.

Leaves and small branches can protrude into the windows.

Strategies to overcome the above problems:

• Providing a buffer zone between the building and trees/vegetation.
• Promote indoor environmental quality by protecting buildings from dirt and moisture.
  • Installing walk-off mats at entrances.
  • Textured paving materials instead of gravel.
• Proper selection of landscaping materials and plants.