As required by the Energy Conservation and Production Act, the U.S. Department of Energy (DOE) has established ANSI/ASHRAE/IESNA Standard 90.1-2004, "Energy Standard for Buildings Except Low-Rise Residential Buildings," as the commercial building reference for state building energy codes.

The DOE has determined the standard would achieve greater energy efficiency in buildings subject to the code than the 1999 edition. The quantitative analysis of the energy consumption of buildings built to Standard 90.1–2004, as compared with buildings built to Standard 90.1–1999, indicates national source energy savings of approximately 13.9% of commercial building energy consumption.

Site energy savings are estimated to be approximately 11.9%. As a result of this positive determination regarding Standard 90.1–2004, each state is required to certify that it has reviewed the provisions of its commercial building code regarding energy efficiency and updated, as necessary, its code to meet or exceed Standard 90.1–2004. State certifications or requests for extensions are required on or before Dec. 30, 2010.