Ecofutures Building Inc. is familiar with firsts. In 2005 Ecofutures built Boulder, Colorado's first net-zero-energy home. In 2008 when the U.S. Department of Energy issued its Builders Challenge, Ecofutures became the first builder to qualify with a score literally off the scale, a "minus three" on the Home Energy Rating System (HERS) index, which is the foundation for the DOE's E-Scale. In March 2009, Doub completed a second net-zero-energy home that qualified for the Builders Challenge with another -3 HERS score.
Over 3,100 people have toured Ecofutures' first Builders Challenge house, where company president Eric Doub lives with his family. The 4,600-square-foot, five-bedroom home has been equipped with extensive energy monitoring equipment. (Data can be viewed at www.ecofuturesbuilding.com/systemsmonitoring.) Ecofutures installs energy monitoring systems in all its new and renovated homes.
A Tour of Energy Efficiency
The wall assembly includes 2x6 16-inch on-center framing filled completely with 7 inches of Icynene spray-foam insulation and 1-inch rigid exterior EPS insulation. Insulated concrete forms create basement walls with an R-30 rating.
The attic is insulated to R-45 with Icynene foam sprayed on the underside of the roof decking, which insulates and air seals the attic while preventing thermal bridging between the conditioned space and the outdoors.
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