Department of Energy Affirms 2024 IECC for Increased Energy Efficiency, Mandating State Review by December 2026
The U.S. Department of Energy (DOE) has issued an affirmative determination for the 2024 International Energy Conservation Code (IECC), confirming that it significantly increases building energy efficiency. This determination, published in the Federal Register on December 30, 2024, found that the 2024 IECC achieves national average residential savings of 7.80% in site energy, 6.80% in source energy, and 6.60% in annual energy costs compared to the 2021 IECC. Following this affirmative determination, federal statute under Title III of the Energy Conservation and Production Act (ECPA) mandates that each state must review its residential energy code within two years. This means states are required to certify by December 30, 2026, whether they will update their codes to meet or exceed the efficiency standards set by the 2024 IECC. The IECC, a model building energy code published triennially by the International Code Council (ICC), establishes minimum baseline efficiency standards for various building component...
