ANSI/ASHRAE/IES Standard 90.1-2016

On July 25, 2017, DOE issued a preliminary determination that Standard 90.1-2016 would achieve greater energy efficiency in buildings subject to the code. DOE estimates national savings in commercial buildings of approximately:

  • 8.2% energy cost savings
  • 7.9% source energy savings
  • 6.7% site energy savings

Additional information related to this action, including the official Federal Register publication and docket containing public comments received, is available at

Supporting Analysis

DOE conducted a technical analysis in support of its preliminary determination. This analyses assesses Standard 90.1 compared to the previous edition, and estimates the anticipated energy consumption of buildings that would be required to meet the updated Standard.

With each new edition of ANSI/ASHRAE/IES Standard 90.1, DOE is required by statute to issue a determination as to whether the updated edition will improve energy efficiency in commercial buildings. (42 U.S.C. 6833)

Commercial Buildings

(2)(A) Whenever the provisions of ASHRAE Standard 90.1-1989 (or any successor standard) regarding energy efficiency in commercial buildings are revised, the [DOE] Secretary shall, not later than 12 months after the date of such revision, determine whether such revision will improve energy efficiency in commercial buildings. The [DOE] Secretary shall publish a notice of such determination in the Federal Register.

(B)(i) If the [DOE] Secretary makes an affirmative determination under subparagraph (A), each State shall, not later than 2 years after the date of the publication of such determination, certify that it has reviewed and updated the provisions of its commercial building code regarding energy efficiency in accordance with the revised standard for which such determination was made. Such certification shall include a demonstration that the provisions of such State's commercial building code regarding energy efficiency meet or exceed such revised standard.

(ii) If the [DOE] Secretary makes a determination under subparagraph (A) that such revised standard will not improve energy efficiency in commercial buildings, State commercial building code provisions regarding energy efficiency shall meet or exceed ASHRAE Standard 90.1-1989, or if such standard has been revised, the last revised standard for which the [DOE] Secretary has made an affirmative determination under subparagraph (A).

DOE typically performs a combination of qualitative analysis (i.e., comparison of individual code provisions) and quantitative analysis (i.e., whole-building simulation) in support of its determinations. The outcome of this analysis supports a determination as to whether new provisions improve building energy efficiency, as would be regulated by the updated code.

Previous DOE determinations surrounding building energy codes are available for reference by states and local governments, as well as other interested stakeholders.