Green Achievements

Saving Energy Through Incremental Improvements:

One of the project's goals was to reduce residents' water, gas, and electricity bills by 30 percent in comparison with standard-construction homes in the area. In order to keep costs as low as possible, Atlanta Habitat pursued many small, volunteer-friendly initiatives that incrementally increased energy performance, rather than focusing on bigger-ticket items that individually save more energy. Improving airtightness, locating ducts in an intelligent



• Crumbling, abandoned road behind homes dug up and replaced with 350 pine seedlings

• Site cleaned up and reused, preventing future neglect.

• All trees outside building footprint saved

• Groundcover kept in place on back half of each building lot to minimize stormwater runoff

• New trees planted to provide shade to homes and HVAC equipment


• Washing machines upgraded to ENERGY STAR®-rated models.

• Stormwater management techniques such as swales and silt fences


• Airtightness improved by installing a double layer of foam board on house exteriors; joints were staggered so there were no cracks through both layers

• Air sealing system designed by Southface used to seal areas where different building elements meet

• Ductwork located in semiconditioned crawl space instead of in exterior walls

• Insulated box with sealed lid installed above attic pull-down stairs to eliminate draft and heat gain/loss of standard pull-down stairs

• Duct blaster and blower door tests conducted by Southface.

• Photovoltaic sensor on exterior lights installed to turn lights on and off automatically at dusk/dawn

• Fluorescent lighting

• ENERGY STAR appliances (washing machine and refrigerator) and high-efficiency water heater

• Double-glazed, vinyl-frame, double-hung windows with low-e glass and 30-year warranty (U-value <0.56, solar heat gain coefficient <0.4)

• Increased insulation: ceiling R-30, exterior wall sheathing R-5, crawl space walls R-8, walls R-13

Materials and Resources

• Advanced framing techniques used to reduce materials needed: interior studs 24 inches on center; ladder headers in non-load-bearing walls; fewer two-by-fours at corners to allow more insulation in wall; wall blocking at intersecting wall locations rather than standard tee

• Wood waste reduced by using engineered I-joists, OSB, and trusses

• Off-site framing done at centralized location to reduce waste (panels assembled at Habitat's warehouse)

• Construction waste recycled, including cardboard, wood pallets, scrap aluminum flatgoods, scrap steel, and beverage containers

• All "drops" from the building process reused to make small framing components

• Drywall added to ground as soil amendment

• Siding, roof shingles, and concrete block ground up as base for driveway concrete

• Non-pressure-treated wood waste ground into chips for landscape mulch

• Carpet pad with a minimum of 50% recycled materials

• Durable materials such as Hardie cementitious siding selected

• Flashed windows and doors using 30-lb felt paper installed to prevent rainwater leakage

Health and Comfort

• Crawl space insulated to create semi-conditioned air, keeping house at comfortable temperature

• Zero-volatile organic compound (VOC) paint

• Water heater closet sealed and insulated

• Bathroom exhaust fans installed that switch on at the same time as the light to ensure use way, and working to eliminate drafts aren't necessarily exciting, but get good results at low cost. For example, the living space directly beneath the pull-down attic stairs is often drafty. To minimize the heat gain and loss caused by leakage in this area, an insulated box with a sealed but operable lid was installed over the opening, a simple step that is, however, rarely taken. Air filtration was reduced via numerous actions, including a focus on sealing locations where different elements of the building come in contact with each other, such as oriented strand board (OSB) decking and the bottom wall plate, mud sills and outside bands, and so forth. In addition, every penetration of the building envelope (where wires or pipes pass through it) was sealed with caulk or expandable foam.

Greening the Site: The site design was constrained by the fact that the land had already been platted, so the design could not fully take into account solar access, shading, or natural lighting. However, homes were built far enough apart to allow access to sunlight, and all existing trees outside the building footprints were preserved to provide shading for the houses and their heating, ventilating, and air-conditioning (HVAC) equipment. During construction, each tree was protected by fencing installed around its drip lines. To help minimize stormwater runoff, ground cover on the back part of each lot was preserved during construction, and silt fences were installed around the perimeter of each lot.

The back of the site is adjacent to a recycling company. To create a buffer between the two uses, Atlanta Habitat dug up a crumbling, abandoned road (formerly owned by the recycling company) and planted 350 seedlings to create a 17,000-square-foot long-term natural visual buffer. Houses were sited as close to the front of the site as the code permitted, to provide the largest possible backyard.

Recycling Construction Materials: Significant efforts were made to conserve and recycle construction materials. A tub grinder was used to recycle various building materials on-site. Ground-up shingles, fiber-cement siding, and concrete blocks provided a base for the newly poured concrete driveways. Wood grindings were used for landscaping mulch, and drywall was added to yard dirt. Wood scraps longer than 4 feet were returned to the warehouse to make components such as spacer blocks for framing, mailbox posts, and decorative elements for the front porches. In addition, all steel and aluminum scraps and cardboard packaging were recycled.

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