The U.S. Department of Energy (DOE) recently announced its preliminary determination of energy savings for the 2021 International Energy Conservation Code (IECC), preliminarily affirming that the updated code will increase energy efficiency in residential buildings. The Department’s analysis, performed by Pacific Northwest National Laboratory (PNNL), indicates that buildings meeting the 2021 IECC (as compared to the previous 2018 edition) would result in national average energy savings of approximately:

• 9.38% site energy
• 8.79% source energy
• 8.66% energy cost
• 8.66% carbon emission

Upon publication of an affirmative determination, States are required to certify that they have reviewed the provisions of their residential building code regarding energy efficiency, and make a determination as to whether it is appropriate for them to revise their code to meet or exceed the updated edition of the IECC.