It may be the most well-known standard in the building design and construction industry: ANSI/ASHRAE/IES Standard 90.1, Energy Standard for Buildings, Except Low-Rise Residential Buildings (or more commonly, ASHRAE Standard 90.1). It serves as the basis for many energy codes across the U.S. It is also the energy standard referenced by LEED and other green building certification systems.
Every few years, Standard 90.1 is updated by ASHRAE in cooperation with other organizations. With each new edition, perhaps you have wondered just how much of a difference the incremental changes in the standard would actually make in application?
It turns out that federal government wonders as well. Since 2002, the U.S. Department of Energy (DOE) has contracted comparative analyses of the latest edition of ASHRAE Standard 90.1 versus the most recent previous edition of the standard regarding energy efficiency improvements.
After completing a comparative analysis, the DOE will publish a “determination” memorandum in the Federal Register. The document provides public notice of the DOE’s findings.
Determinations are publicly available on the DOE’s website appear to go back as far as 2002, when the department published a comparative analysis of the 1999 edition to the 1989 edition.