EarthCraft House^TM Integrates Building America Research to Achieve Higher Levels of Energy Savings

April 2005

Energy savings in the Building America program are measures of success, so a recent project with the Southface Energy Institute's energy-efficient EarthCraft House^TM program has piqued great interest. Using performance levels from the Building America program and consulting with Building America partner IBACOS (Integrated Building and Construction Solutions), the Southface Energy Institute will enhance its popular EarthCraft House^TM program to build homes to a greater level of performance.

The EarthCraft House^TM program was created in 1999 as a partnership between the Greater Atlanta Home Builders Association and Southface Energy Institute. A green building initiative that helps builders to build healthier, more energy-efficient homes, the EarthCraft House program has certified more than 2000 homes in five years through its point-based system.

EarthCraft homes are more efficient than conventional construction because of the requirements for air sealing the home. ENERGY STAR^® is a part of the EarthCraft House program and available as an option to builders. ENERGY STAR homes are 30 percent more efficient than the benchmark 1993 Model Energy Code.

Southface Energy Institute increased its interest in Building America research when it worked with IBACOS on the Noisette Community in North Charleston, South Carolina to design homes for the planned sustainable community. In 2004, the two energy-use researchers merged the Noisette Community's performance standards into a checklist that may serve as the base for a new tiered EarthCraft House point system.

In 2005, through research and collaboration with Building America, Southface Energy Institute will establish three tiers of achievement within the point-based green building program. The first tier reflects the current EarthCraft House^TM program with some added requirements to earn points in designated categories such as water heating. In the second tier, homes will meet the standards developed for the Noisette community that achieve greater durability features and demand a higher level of efficiency for larger homes due to the increased shell area and typically higher number of occupants. Homes in the third tier will achieve energy savings of 40% or above the Building America Benchmark.

Homes that will reach the third-tier level are already underway. One of these homes is a 3,200 square foot, three-story home in the Glenwood Park community on the east side of Atlanta, Georgia. The home will be showcased in Southern Living Magazine in August 2005 as an "Idea House" that demonstrates energy-efficient and renewable energy technologies. The house will be open to the public mid-June through early October.

For this Atlanta home, IBACOS worked with the builder to develop the following specifications:

• Two highly efficient HVAC systems located entirely within conditioned space
• Efficient fluorescent lighting in roughly 75% of the house
• R-10 insulated, conditioned crawlspace
• 2x6 framed R-3 foam-sheathed exterior wall filled with Icynene (R-22 total)
• Sealed attic with R-22 insulation (Icynene under roof deck)
• High performance, low-emissivity windows, which reduce solar heat gain
• A tankless Bosch water heater to serve the house and a smaller one for the garage suite.

The house will also incorporate a 1.5 kW photovoltaic (PV) system to generate on-site energy. IBACOS calculates 50% savings compared to the Building America Benchmark for the home with the use of the PV system. Without the PV system, the house will reach 44% savings.

The new tiers of achievement in the EarthCraft House^TM have the potential to bring about advanced performance in thousands of future homes. Southface Energy Institute will use funding from a recent State Energy Program (SEP) Grant through the Georgia Environmental Facilities Authority to advance the program.

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