ANSI/ASHRAE/IESNA Standard 90.1-1999

DOE issued a determination that the ASHRAE/IESNA Standard 90.1-1999 will save energy in commercial buildings. This process was completed and signed on July 15, 2002. View the news release announcing the determination, or the complete determination notice that appeared in the Federal Register on July 15, 2002. (PDF 151 KB).

State Certification

Certifications or Requests for Extension of Deadlines, with regard to Standard 90.1-1999, were due at DOE on or before July 15, 2004.

As required by the Act, all states have two years to adopt Standard 90.1-1999 or upgrade their existing commercial building codes to meet or exceed its requirements.

Quantitative Analysis

A quantitative analysis of the estimated differences between the 1989 and 1999 editions of Standard 90.1 was performed to inform and support the final determination. An Excel spreadsheet containing the analysis can be downloaded at no cost (ZIP 5.8 MB).

An Explanation of the Analysis and Spreadsheet is available to assist in understanding the analysis.

Detailed Textual Analysis

A Detailed Textual Analysis of the estimated differences between the 1989 and 1999 editions of Standard 90.1 was been performed to inform and support the final determination (PDF 87 KB).