Sustainability is the process applied to our quest to sustain economic growth while maintaining our long-term environmental health. Sustainability means designing structures that take advantage of technological advancements to create eco-friendly products. Inert-gas-filled insulated windows, engineered-wood products made from scrap wood shavings, sawdust and assorted wood fibers, and thermal break window frames that keep the cold and hot air out are all examples of sustainable products. These products provide the owner and occupants with the following benefits:
- Reduced maintenance and replacement costs over the life of the building
- Energy conservation
- Improved occupant health
- Productive working environment
Sustainable products incorporated into the building should follow these selection guidelines:
- Recycled content
- Natural, plentiful, or renewable materials
- Products manufactured by a resource-efficient process
- Locally available products
- Salvaged, refurbished, or remanufactured products
- Reusable or recyclable products
- Durable products
Using sustainable materials can also improve the indoor working environment and save money. Consider these advantages:
- Materials that emit few or no carcinogens or irritants, as demonstrated by the manufacturer’s long-term testing results
- Minimal chemical emissions from volatile organic compounds (VOC) that out-gas (continue to emit chemical vapors after installation)
- Moisture-resistant materials that are not easily susceptible to mold growth
- Materials that are easily maintained and require simple nontoxic cleaners
- Equipment systems that promote healthy indoor air quality (IAQ) by identifying indoor air pollutants
- Products and systems that help reduce water consumption
The sustainable approach to design would include requirements to do the following:
- Simplify construction details.
- Utilize repetitive details and components.
- Standardize design components.
- Incorporate accurate dimensions in the design, as some product and material sizes many have been reduced.
- Simplify building systems so future expansion projects can take advantage of simplified designs or components.
- Consider occupant safety and worker productivity gains in the new design.
- Investigate more efficient and environmentally sensitive ways to bring underground utilities into the site with the least disruption to the existing terrain.
- Consider other ways of disposing of site drainage onsite rather than offsite.
- Adjust new site contours to provide for a balanced site where no offsite fill or off-site disposal of surplus soils is required.
- Optimize dimensions to utilize a standard product size.
- Minimize plumbing pipe and HVAC ductwork bends to reduce liquid and air friction.
- Select fittings and fasteners that permit quick assembly.
- Select sealants with the least environmental impact and longest life.
- Investigate ways to accumulate salvaged and waste materials for recycling.
- Consider donating surplus materials to a nonprofit organization such as Habitat for Humanity.
- Deconstruct all existing structures with substantial recoverable materials and dispose of them to recyclers.
When designing a new green structure, a number of goals must be set. The site must meet or exceed standards for sedimentation control and erosion:
- Prevent the loss of soil during excavation and construction due to surface water drainage; keep dust down and cover large stored piles of earth to prevent wind erosion.
- Prevent the silting up of existing storm drains in the immediate area by constructing erosion and silt fence enclosures around areas to be excavated.
- Prevent the siltation of existing nearby streams or waterways by installing erosion and silt fencing around those streams adjacent to areas to be excavated.
- Protect topsoil piles for reuse. (Topsoil piles are generated early in the construction process as soil is stripped during rough grading operations; respreading is one of the last operations, commencing as landscaping is put in place.)
The site utilities should reduce soil erosion during excavation of trenches and contain storm water runoff:
- Plan infiltration swales and basins during trenching operations to contain surface water.
- Retain or recharge existing water tables by minimizing site disturbances; leave as many trees as possible; use existing vegetation and retain natural contours.
- Consider a design to store roof runoff when the building has been completed; it can be used as gray water or reclaimed wastewater.
- Investigate a small onsite, state-of-the-art treatment plant to recycle reclaimed water.
An open-space and landscaping program can accommodate the following:
- Protect trees during construction; they enhance property values and lower cooling loads.
- Consider indigenous landscaping; it supports natural wildlife and plantings and lowers the level of irrigation as well as the need to fertilize and apply chemical treatment.
- Minimize pesticide use by installing weed cloth; use mulches and planting species that create dense planting beds.
Site -circulation and transportation programs should meet these objectives:
- Encourage carpooling.
- Provide areas for people to store bicycles during working hours.
- Encourage the use of public transportation by instituting a program of incentives.