The 2009 International Residential Code and the American Recovery and Renewal Act of 2009.

The Department of Energy has performed a comparative review of the provisions of the 2009 International Energy Conservation Code and the 2009 International Residential Code, in response to a number of requests from States and other interested parties. These queries have been made in response to Governor's assurances required by Section 410 of the Recovery Act and progress reports on those assurances. The review concluded that the 2009 International Residential Code is not equivalent to the 2009 International Energy Conservation Code, but that if the 2009 International Residential Code was adopted with certain amendments, it would be equivalent. This analysis is intended to provide technical assistance for those interested in this matter.

Update: September 23, 2009

The analysis above contains revisions to the previously posted analysis to correct errors in the amendments needed to IRC Table N1102.1.1. It also presents a more detailed analysis of the impact of glazed fenestration solar heat gain coefficients (SHGC) in climate zone 3.