Department of Energy: New Model Residential Energy Code Includes Increases in Efficiency Requirements

The Department of Energy (DOE) today issued a positive determination that the 2021 International Energy Conservation Code (IECC) contains new requirements that result in an incremental increase in energy efficiency in residential buildings.

The IECC is part of a family of model building codes published by the International Code Council (ICC) and adopted in many jurisdictions around the country, often with specific amendments based on local market and climatic conditions.

DOE reports it came to this conclusion by conducting a technical analysis evaluating the impacts of the updated code relative to the 2018 IECC edition.

DOE estimates national savings of approximately:

• 9.38% site energy savings
• 8.79% source energy savings
• 8.66% energy cost savings
• 8.66% carbon emissions

DOE is required by law to issue a determination as to whether the latest version of the IECC includes increases in energy efficiency compared to the previous edition of the code. DOE has one year to publish a determination in the Federal Register after each new edition of the standard/code is published.

States will now be required to certify that they have reviewed the provisions of their residential building code regarding energy efficiency, and made a determination as to whether it is appropriate for them to revise their code to meet or exceed the updated edition of the IECC.State certifications for the 2021 IECC must be submitted by July 21, 2023.

DOE’s determination is consistent with the analysis released by Home Innovation Research Labs last month that showed similar increases in efficiency. The Home Innovation report also contains the associated cost and cost-effectiveness metrics for the changes in efficiency requirements in the 2021 IECC.