Determinations

Final Determination on ASHRAE Standard 90.1-2010

On October 19, 2011, DOE issued a final determination that ASHRAE Standard 90.1-2010 would achieve greater energy efficiency in buildings subject to the standard than if they were built to ASHRAE Standard 90.1-2007.

View the complete final determination notice that appeared in the Federal Register on October 19, 2011.

View the complete preliminary determination notice that appeared in the Federal Register on July 20, 2011.

State Certification

This final determination is being published before the two year deadline for states to file a certification for the 2007 positive determination; therefore, a state may file just one certification to address both determinations. The certification must include a demonstration that the provisions of the state's commercial building energy code or standard regarding energy efficiency meet or exceed ASHRAE Standard 90.1-2010 and be filed by July 20, 2013.

Certifications or Requests for Extension of Deadlines, solely with regard to ASHRAE Standard 90.1-2010, will be due to DOE by October 18, 2013. All states have two years to adopt ASHRAE Standard 90.1-2010 or upgrade their existing commercial building codes or standards to meet or exceed its requirements.

Quantitative Analysis

A quantitative analysis of the estimated differences between the 2007 and 2010 editions of ASHRAE Standard 90.1 was performed to inform and support the final determination. The quantitative analysis of the energy consumption of buildings built to ASHRAE Standard 90.1-2010, as compared with buildings built to ASHRAE Standard 90.1-2007, indicates national source energy savings of approximately 18.2% of commercial building energy consumption.

Detailed Textual Analysis

A detailed textual analysis of the estimated differences between the 2007 and 2010 editions of ASHRAE Standard 90.1 was performed to inform and support the final determination.


With each new edition of ASHRAE Standard 90.1, DOE issues a determination whether the new edition will improve energy efficiency in commercial buildings. The determination is based on analysis by BECP and is required by Section 304 of the Energy Conservation and Production Act (ECPA, Public Law 94-385), as modified by the Energy Policy Act of 1992 (EPAct 1992). DOE has one year to publish the determination after the newest edition of the standard is published. Determination results are published in the Federal Register.

If DOE finds that the newest version of ASHRAE Standard 90.1 is more energy efficient than the previous version, states are required by EPAct 1992 to certify that their building energy codes or standards meet or exceed the requirements of the new standard within two years.

Once DOE issues an affirmative determination, it must provide technical assistance and incentive funding to states to:

  • Review and update state energy codes or standards
  • Implement, enforce, and evaluate compliance with state energy codes or standards

DOE also must permit certification extensions if the state demonstrates a good faith effort to comply with its requirements and has made significant progress toward compliance.

Section 304 of ECPA, as amended by Section 101 of EPAct 1992, requires

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).

If changes are straightforward, with the preponderance of individual changes being obvious improvements, DOE will make its determination based on a qualitative assessment of the changes. If changes are nuanced or involve a combination of obvious improvements and obvious regressions, DOE will conduct energy analyses of the changes. DOE uses the following three approaches to analysis, depending on the magnitude and type of code changes:

  • Use existing impact estimates developed for industry or other programs
  • Conduct limited simulation analyses of affected building elements in relevant climates
  • Conduct comprehensive whole-building modeling across climate zones with weighting factors for the major variables (building type, system types, fuel types, etc.).

DOE has typically performed both a qualitative analysis (text comparison) and quantitative analysis (whole building simulation) for commercial determinations.

The outcome of this analysis supports a determination as to whether the new code or standard improves energy efficiency, and which is published in the Federal Register within one year of the new standard's publication.

Final Determination on 2012 IECC

On May 17, 2012, DOE issued a final determination that the 2012 IECC would achieve greater energy efficiency in low-rise residential buildings than the previous editions of the IECC.

View the complete final determination notice that appeared in the Federal Register on May 17, 2012.

After a regulatory action has been issued, Section 6(a)(3)(E) of EO 12866 requires agencies to identify in a complete, clear, and simple manner, the substantive changes between the draft of the final determination submitted to "The Office of Management and Budget's Office of Information and Regulatory Affairs (OIRA)" for review and this final determination, and identify those changes in this determination that were made at the suggestion or recommendation of OIRA. This OMB compare document is intended to comply with this requirement.

View the complete preliminary determination notice that appeared in the Federal Register on October 19, 2011.

State Certification

This final determination is being published before the two year deadline to file a certification for the 2009 IECC positive determination; therefore, a state may file just one certification to address both determinations. The certification must include a demonstration that the provisions of the State's residential building energy code regarding energy efficiency meet or exceed the 2012 IECC and be filed by July 19, 2013.

Certifications or Requests for Extension of Deadlines, solely with regard to the 2012 IECC, will be due to DOE on May 17, 2014. All states have two years to adopt the 2012 IECC or upgrade their existing residential building codes to meet or exceed its requirements.


With each new edition of the IECC, DOE issues a determination whether the new edition will improve energy efficiency in residential buildings. The determination is based on analysis by BECP and is required by Section 304 of the Energy Conservation and Production Act (ECPA, Public Law 94-385), as modified by the Energy Policy Act of 1992 (EPAct 1992). DOE has one year to publish the determination after the newest edition of the code is published. Determination results are published in the Federal Register.

If the analysis shows that the revised code is more energy efficient than the earlier code, each state is required by EPAct 1992 to certify that it has reviewed its residential building energy code regarding energy efficiency and made a decision as to whether it is appropriate for that state to revise its residential building code to meet or exceed the revised code.

DOE may provide technical assistance to states to improve and implement state residential building energy codes or to otherwise promote the design and construction of energy efficient residential buildings.

DOE also may provide incentive funding to states to implement stronger residential building energy codes. The amount of funding will be based on the actions proposed by the state to improve and implement residential energy codes and to promote energy efficiency through the use of energy codes.

Section 304 of ECPA, as amended by Section 101 of EPAct 1992, requires

Residential Buildings

(5)(A) Whenever CABO* Model Energy Code1, 1992, (or any successor of such code) is revised, the [DOE] Secretary shall, not later than 12 months after such revision, determine whether such revision would improve energy efficiency in residential buildings. The [DOE] Secretary shall publish notice of such determination in the Federal Register.

(B) 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 the provisions of its residential building code regarding energy efficiency and made a determination as to whether it is appropriate for such State to revise such residential building code provisions to meet or exceed the revised code for which the [DOE] Secretary made such determination.

*Council of American Building Officials (a predecessor to the ICC, CABO was responsible for development of the Model Energy Code [MEC]).

1 Early residential energy code revisions were referred to as the Model Energy Code; more contemporary energy codes are referred to as the International Energy Conservation Code® or IECC.

If changes are straightforward, with the preponderance of individual changes being obvious improvements, DOE will make its determination based on a qualitative assessment of the changes. If changes are nuanced or involve a combination of obvious improvements and obvious regressions, DOE will conduct energy analyses of the changes. DOE uses the following three approaches to analysis, depending on the magnitude and type of code changes:

  • Use existing impact estimates developed for industry or other programs
  • Conduct limited simulation analyses of affected building elements in relevant climates
  • Conduct comprehensive whole-house modeling across climate zones with weighting factors for the major variables (single vs. multifamily, foundation types, fuel types, etc.).

The outcome of this analysis informs a determination as to whether the new code or standard improves energy efficiency, published in the Federal Register within one year of the new standard's publication.

Previous versions of determinations published in the Federal Register are available as part of historical records that may be useful to states and local entities.