Preliminary analysis released by the U.S. Department of Energy (DOE) finds that the residential provisions of the 2021 edition of the International Energy Conservation Code (IECC) are 9.38 percent more efficient than the 2018 edition and reduce greenhouse gas (GHG) emissions by 8.66 percent. The International Code Council has developed the IECC for over three decades; it is one of the International Codes, the most widely used and adopted set of building safety codes in the world. With this new analysis, the IECC has seen a 40 percent improvement in energy savings starting from the 2006 edition. 

Publication of each new edition of the IECC triggers a Congressionally mandated review of the code by DOE to determine that the new edition saves energy over the prior edition. In his first day in office, President Biden issued an Executive Order expediting DOE's analysis. The determination is now open for a 30-day public review period. Once finalized, the determination triggers requirements for states to review their residential energy codes to determine if updates are appropriate. States must then certify to DOE that they have undertaken such a review. 

Both the Biden Administration and the Code Council have recognized the key role energy codes play in reducing GHG emissions and achieving the recently announced nationally determined contribution (NDC) of GHG reductions of 50 to 52 percent compared to a 2005 baseline by 2030. 

"As communities around the world work to reduce greenhouse gases and adapt to a changing climate, energy codes are an essential tool in reducing the impacts of buildings," said Code Council Chief Executive Officer Dominic Sims, CBO. "DOE's analysis confirms the significant contributions of the IECC to date. Adoption and effective implementation by state and local governments are critical next steps towards ensuring the IECC's benefits are realized. We look forward to continued work with DOE and other agencies in assisting states and localities in their efforts to address climate change and reduce residential energy bills." 

The Code Council will continue the significant progress captured in the 2021 IECC through new commitments embedded in the scope and intent of the 2024 edition and beyond including improvements from edition to edition; the inclusion of zero energy building pathways today and paths to zero energy by 2030; and the inclusion of additional GHG reduction strategies like electric vehicle charging and building electrification. These commitments were announced in a new energy efficiency and GHG reduction framework issued in March, Leading the Way to Energy Efficiency: A Path Forward on Energy and Sustainability to Confront a Changing Climate.