2015 Energy Code Could Back Off on Envelope Requirements

Mechanical tradeoffs were first eliminated from the code in 2009—a key change calculated to help the 2009 standard see a projected efficiency gain of 15% over the 2006 code, according to the U.S. Department of Energy. The tradeoffs were removed based on the argument that gains from installing an efficient HVAC system or furnace could be lost if equipment were replaced by a worse-performing system, while a well-insulated house with a tight building envelope would reap efficiency benefits for the building’s lifetime.

However, the National Association of Home Builders (NAHB) objected to this change and argued that at a time when the building industry is strained by cost, builders need flexibility to pick where to invest; installing energy-efficient equipment could be more cost-effective than adding labor-intensive insulation requiring higher levels of expertise, the group contends.