Building sustainably is an opportunity to use natural resources efficiently, create healthier buildings, build a better environment, and provide cost savings.
What Makes a Building SUSTAINABLE?
A sustainable building is one that is built and operated in a resource-efficient manner, and in a way that is concerned with living organisms and their physical surroundings. The main ways sustainable buildings do this is:
- Energy and Resource Conservation – use minimal energy, water, and other resources to reduce the overall impact to the environment.
- Passive Solar Energy – Use thermal mass to capture the suns energy during the day and give off heat during the night.
- Renewable Solar Energy – Use photovoltaic panels to turn the sun’s energy into electricity.
- Healthy and sustainable building materials – People have been building with earth for thousands of years: Living With the Land
What Are the Elements of Green Buildings?
Below are some green building practices.
Siting
- Orient the building to maximize the sun’s energy. Use large windows on the South facade together with thermal mass floors to capture the sun’s passive solar energy. Properly designed overhangs can block the sun during the hot months.
- Protect and retain existing landscaping and natural features. Select plants that have low water and pesticide needs, and generate minimum plant trimmings. Use compost and mulches. This will save water and time.
- Recycled content paving materials, furnishings, and mulches help close the recycling loop.
Energy Efficiency
The following strategies can help buildings reach energy efficiency levels:
- Use a properly sized and energy-efficient heat/cooling system
- Use a thermally efficient building shell.
- install high R-value wall and ceiling insulation. We recommend R70 roofs, R50 walls, and R8 quad paned windows with heat recovery ventilators.
- Maximize light colors for roofing and wall finish materials
- Use minimal glass on east and west exposures.
- Minimize the electric loads from lighting, equipment, and appliances.
- Consider alternative energy sources such as photovoltaics and fuel cells that are now available in new products and applications. Renewable energy sources are a great emerging technology for the future.
- Computer modeling is extremely useful for optimizing the design and use of electrical and mechanical systems as well as the building shell.
- Passive design strategies can dramatically affect building energy performance. These measures include building shape and orientation, passive solar design, and the use of natural lighting.
- Develop strategies to provide natural lighting. Studies have shown that it has a positive impact on productivity and well being.
- Install high-efficiency lighting systems with advanced lighting controls. Include motion sensors tied to dimmable lighting controls. Task lighting reduces general overhead light levels.
Materials Efficiency
- Select sustainable construction materials and products by evaluating several characteristics such as reused and recycled content, zero or low off gassing of harmful air emissions, zero or low toxicity, sustainably harvested materials, high recyclability, durability, longevity, and local production. Such products promote resource conservation and efficiency. Using recycled-content products also helps develop markets for recycled materials that are being diverted from California’s landfills, as mandated by the Integrated Waste Management Act.
- Use dimensional planning and other material efficiency strategies. These strategies reduce the amount of building materials needed and cut construction costs. For example, design rooms on 4-foot multiples to conform to standard-sized wallboard and plywood sheets.
- Reuse and recycle construction and demolition materials. For example, using inert demolition materials as a base course for a parking lot keeps materials out of landfills and costs less.
- Require plans for managing materials through deconstruction, demolition, and construction.
- Design with adequate space to facilitate recycling collection and to incorporate a solid waste management program that prevents waste generation.
Water Efficiency
- Design for dual plumbing to use recycled water for toilet flushing or a gray water system that recovers rainwater or other nonpotable water for site irrigation.
- Minimize wastewater by using ultra low-flush toilets, low-flow shower heads, and other water conserving fixtures.
- Use recirculating systems for centralized hot water distribution.
- Install point-of-use hot water heating systems for more distant locations.
- Use a water budget approach that schedules irrigation using the California Irrigation Management Information System data for landscaping.
- Meter the landscape separately from buildings. Use micro-irrigation (which excludes sprinklers and high-pressure sprayers) to supply water in nonturf areas.
- Use state-of-the-art irrigation controllers and self-closing nozzles on hoses.
Occupant Health and Safety
Recent studies reveal that buildings with good overall environmental quality can reduce the rate of respiratory disease, allergy, asthma, sick building symptoms, and enhance worker performance. The potential financial benefits of improving indoor environments exceed costs by a factor of 8 and 14.
Choose construction materials and interior finish products with zero or low emissions to improve indoor air quality. Many building materials and cleaning/maintenance products emit toxic gases, such as volatile organic compounds (VOC) and formaldehyde. These gases can have a detrimental impact on occupants’ health and productivity.
Provide adequate ventilation and a high-efficiency, in-duct filtration system. Heating and cooling systems that ensure adequate ventilation and proper filtration can have a dramatic and positive impact on indoor air quality.
Prevent indoor microbial contamination through selection of materials resistant to microbial growth, provide effective drainage from the roof and surrounding landscape, install adequate ventilation in bathrooms, allow proper drainage of air-conditioning coils, and design other building systems to control humidity.
Building Operation and Maintenance
Green building measures cannot achieve their goals unless they work as intended. Building commissioning includes testing and adjusting the mechanical, electrical, and plumbing systems to ensure that all equipment meets design criteria. It also includes instructing the staff on the operation and maintenance of equipment.
Over time, building performance can be assured through measurement, adjustment, and upgrading. Proper maintenance ensures that a building continues to perform as designed and commissioned.
What Are the Economic Benefits of Green Buildings?
A green building can save money through lower operating costs over the life of the building. The green building approach applies a project life cycle cost analysis for determining the appropriate up-front expenditure. This analytical method calculates costs over the useful life of the asset. Some benefits, such as improving occupant health, comfort, productivity, reducing pollution and landfill waste are not easily quantified. Consequently, they are not adequately considered in cost analysis.
Even with a tight budget, many green building measures can be incorporated with minimal or zero increased up-front costs and they can yield enormous savings. Cost savings can only be fully realized when they are incorporated at the project’s design phase.