Environmental Building Glossary

AAC—autoclaved, aerated concrete (AAC) is a lightweight, precast cement building material that conserves cement while retaining its highly insulative properties. AAC blocks and wall panels have been used extensively in Europe.

Active solar power—technologies that convert solar energy into heat or help move air for ventilation and cooling. Active solar systems use mechanical or electrical equipment such as pumps and fans to increase the usable solar energy. These systems can include ground or roof-mounted solar panels that use liquid- or air-based collectors and transfer energy directly to living spaces or a storage tank. Photovoltaic cells can be used to generate electricity.

Conservation areas—Tracts of land that have been protected or set aside to preserve natural features, wildlife, flora and fauna. A conservation area may be a nature reserve or a park that has restrictions on development or other activities that may harm its unique ecosystem.

Erosion control—Erosion is the removal of soil by wind or water and is the largest source of pollution for lakes, streams and rivers. Erosion can be accelerated by construction, but this risk can be controlled by using construction methods that minimize soil excavation, by supporting embankments with retaining walls, and by restoring site disturbances with native vegetation.

Engineered lumber—Wood that is manufactured by bonding together wood strands, veneers, lumber or fiber to produce a stronger and more uniform composite. Engineered lumber does not require the use of mature growth trees and typically results in less production and job-site waste.

Engineered stone—Solid slabs made primarily from quartz crystals, nature’s most abundant mineral next to water, bonded with a small amount of pigment and man-made resins. Engineered stone is more environmentally friendly than other quarried stones because of its abundance, easy extraction, and reduced transportation needs.

Geothermal heat pump—This system uses the earth’s natural warmth (a constant of about 50 degrees) to help support heating and cooling needs. Loops of piping are buried under the frostline and circulate liquid that absorbs the earth’s heat in the winter; the heated liquid is converted to warm air by a heat exchanger. The process is reversed in warmer summer months. Geothermal energy is nonpolluting and renewable and can save homeowners as much as 50 percent on their heating and cooling bills.

Greywater systems—Household wastewater generated by showers and sinks can be captured and filtered in manual, gravity-fed or electric systems for reuse in landscaping and even flushing toilets. Greywater systems reduce stress on septic systems and municipal sewer systems and also reduce dependence on watersheds.

ICFs—insulated concrete forms (ICFs) are pre-cast concrete-and-foam blocks used to construct durable and highly insulated walls. ICFs may have a high recycled content and are moisture, pest and wind resistant.

Indoor air quality—also known as indoor environmental quality (IEQ) and refers to the quality of the air and indoor environment. IEQ includes issues relating to mold and moisture, radon, temperature fluctuations, and air pollution caused by combustion sources, offgassing of building materials and interior finishes, and household cleaning products and pesticides. Mechanical ventilation, air purification and filtration can greatly improve indoor air quality and comfort.

Naturescaping—landscaping that incorporates native plants that are hardy, require less water and maintenance, and are generally pest resistant. Naturescaped areas require fewer or no chemical fertilizers and pesticides and, therefore, help prevent polluted stormwater from entering our waterways.

Passive solar design—building design that uses non-mechanical techniques to capture the sun’s energy for heating, cooling and lighting. Key elements of solar design include solar and wind orientation of the house, thermal mass, open floor plans, and appropriate ventilation and window placement. Wing walls, overhangs and thermal chimneys can enhance heating and cooling.

Pre-cast concrete walls—factory-made concrete wall sections up to 12 feet long filled with rigid insulation. These walls are typically used for earth-bermed basements and lower floors. Pre-cast concrete walls conserve concrete and typically do not require a footer.

Radiant flooring—a heating system that produces radiant energy from hot water that is continually circulated through a flexible network of tubes installed underneath floor surfaces. The water may be heated by a gas, oil, electric or solar water heater. Radiant flooring provides very efficient, quiet and comfortable heat. It is especially well-suited for hard flooring surfaces such as wood, tile, concrete or stone.

Rain gardens—Landscaped areas designed to soak up stormwater runoff from roofs, driveways, sidewalks and lawns. Planted with deep-rooted native plants and grasses, rain gardens slow and filter runoff, reduce erosion, recharge groundwater and help keep contaminants such as fertilizer and pesticides out of the water supply.

Reclaimed/salvaged lumber—Lumber removed from existing homes or buildings that is re-milled for use in new construction. Reclaimed lumber is prized for the antique beauty of its old-growth timbers as well as for its conservation of forest resources.

SIPs—structural insulated panels (SIPs) are pre-built wood-and-foam panels that provide excellent insulation, low job-site waste, and reduced framing time.

Sustainable design—An approach that views human civilization as intricately connected with the natural world. Sustainable design supports human health as well as the health of surrounding air, water, soils, wildlife and vegetation. Sustainable design emphasizes the use of low-impact building materials, energy efficiency and high-quality, durable construction to reduce negative environmental impacts.