This is an excerpt from EERE Network News, a weekly electronic newsletter.

July 21, 2010

Report: Home Size is Declining, Energy Efficiency a Factor

The size of new U.S. single-family homes completed in 2009 declined, dropping to a nationwide average of 2,438 square feet and reversing trend of the past three decades, according to a National Association of Home Builders (NAHB). New single-family homes were almost 100 square feet smaller in 2009 than they were in 2007, according to recently released U.S. Census Bureau data. One reason for the drop, NAHB noted, was homeowners' desire to keep energy costs in check. This growing energy-efficiency consciousness is one of many trends that the association said was likely to continue.

Despite the tendency towards a smaller footprint, overall energy usage has been growing. One reason could be the spread of air conditioning. Census Bureau data show that less than half of all new single-family homes completed in 1973 had air conditioning while nearly nine-out-of-ten new homes were air conditioned. Not surprisingly, there are regional differences in those nationwide findings. The proportion of homes with air conditioning ranged from a low of 69% in the West to a high of 99% in the South. The Northeast and Midwest were at 75% and 90%, respectively.

Still, even as energy use climbs, so does energy efficiency. "Residential Energy Consumption Survey," a U.S. Energy Information Administration (EIA) report released in 2005, confirms that while both floor size and overall energy consumption been trending upwards for decades, energy consumption per square foot has been dropping. The survey shows that new households were smallest from 1970 to 1979, averaging 1,863 square feet. They steadily increased through 2005, according to the EIA report. Likewise, overall household energy consumption was lowest from 1980 to 1989, but has been rising ever since. However, even as residences have grown, the amount of energy used per square foot has declined from 51.8 Btu per square foot before 1940 to only 33.4 Btu per square foot in structures built from 2000 to 2005. See the NAHB press release and page three of the EIA 2005 “Residential Energy Consumption Survey” (PDF 51 KB). Download Adobe Reader.