Publications

Section 304(a) of the Energy Conservation and Production Act, as amended, directs the U.S. Secretary of Energy to review the International Energy Conservation Code (IECC)1 and make a determination as to whether updated editions would improve energy efficiency in residential buildings. The IECC is developed by the International Code Council (ICC) through an established industry review and consensus process with updated editions typically published every 3 years. The U.S. Department of Energy (DOE) reviews the energy saving impacts of updated code editions and publishes its findings in the Federal Register. The DOE determination and accompanying technical analysis serve as useful guidance to state and local governments as they review and update their building codes. 

The most recent edition, the 2024 IECC, was published in August 2024, triggering the DOE review and determination process.2 DOE and Pacific Northwest National Laboratory (PNNL) conducted a technical analysis to determine energy savings for the 2024 IECC (ICC 2024) residential provisions relative to the previous edition, the 2021 IECC (ICC 2021). This report documents the methodology used to conduct the analysis and summarizes the results. 

These analyses evaluate the cost-effectiveness of the prescriptive path of the 2018 edition of the International Energy Conservation Code (IECC), relative to the 2015 IECC with amendments for all 50 states and the District of Columbia. The analysis covers one- and two-family dwelling units, townhouses, and low-rise multifamily residential buildings covered by the residential provisions of the 2018 IECC.

These analyses evaluate the cost-effectiveness of the prescriptive path of the 2018 edition of the International Energy Conservation Code (IECC), relative to the 2015 IECC with amendments for all 50 states and the District of Columbia. The analysis covers one- and two-family dwelling units, townhouses, and low-rise multifamily residential buildings covered by the residential provisions of the 2018 IECC.

These analyses evaluate the cost-effectiveness of the prescriptive path of the 2018 edition of the International Energy Conservation Code (IECC), relative to the 2015 IECC with amendments for all 50 states and the District of Columbia. The analysis covers one- and two-family dwelling units, townhouses, and low-rise multifamily residential buildings covered by the residential provisions of the 2018 IECC.

These analyses evaluate the cost-effectiveness of the prescriptive path of the 2018 edition of the International Energy Conservation Code (IECC), relative to the 2015 IECC with amendments for all 50 states and the District of Columbia. The analysis covers one- and two-family dwelling units, townhouses, and low-rise multifamily residential buildings covered by the residential provisions of the 2018 IECC.

These analyses evaluate the cost-effectiveness of the prescriptive path of the 2018 edition of the International Energy Conservation Code (IECC), relative to the 2015 IECC with amendments for all 50 states and the District of Columbia. The analysis covers one- and two-family dwelling units, townhouses, and low-rise multifamily residential buildings covered by the residential provisions of the 2018 IECC.

These analyses evaluate the cost-effectiveness of the prescriptive path of the 2018 edition of the International Energy Conservation Code (IECC), relative to the 2015 IECC with amendments for all 50 states and the District of Columbia. The analysis covers one- and two-family dwelling units, townhouses, and low-rise multifamily residential buildings covered by the residential provisions of the 2018 IECC.

These analyses evaluate the cost-effectiveness of the prescriptive path of the 2018 edition of the International Energy Conservation Code (IECC), relative to the 2015 IECC with amendments for all 50 states and the District of Columbia. The analysis covers one- and two-family dwelling units, townhouses, and low-rise multifamily residential buildings covered by the residential provisions of the 2018 IECC.

These analyses evaluate the cost-effectiveness of the prescriptive path of the 2018 edition of the International Energy Conservation Code (IECC), relative to the 2015 IECC with amendments for all 50 states and the District of Columbia. The analysis covers one- and two-family dwelling units, townhouses, and low-rise multifamily residential buildings covered by the residential provisions of the 2018 IECC.

These analyses evaluate the cost-effectiveness of the prescriptive path of the 2018 edition of the International Energy Conservation Code (IECC), relative to the 2015 IECC with amendments for all 50 states and the District of Columbia. The analysis covers one- and two-family dwelling units, townhouses, and low-rise multifamily residential buildings covered by the residential provisions of the 2018 IECC.

These analyses evaluate the cost-effectiveness of the prescriptive path of the 2018 edition of the International Energy Conservation Code (IECC), relative to the 2015 IECC with amendments for all 50 states and the District of Columbia. The analysis covers one- and two-family dwelling units, townhouses, and low-rise multifamily residential buildings covered by the residential provisions of the 2018 IECC.

These analyses evaluate the cost-effectiveness of the prescriptive path of the 2018 edition of the International Energy Conservation Code (IECC), relative to the 2015 IECC with amendments for all 50 states and the District of Columbia. The analysis covers one- and two-family dwelling units, townhouses, and low-rise multifamily residential buildings covered by the residential provisions of the 2018 IECC.

These analyses evaluate the cost-effectiveness of the prescriptive path of the 2018 edition of the International Energy Conservation Code (IECC), relative to the 2015 IECC with amendments for all 50 states and the District of Columbia. The analysis covers one- and two-family dwelling units, townhouses, and low-rise multifamily residential buildings covered by the residential provisions of the 2018 IECC.

These analyses evaluate the cost-effectiveness of the prescriptive path of the 2018 edition of the International Energy Conservation Code (IECC), relative to the 2015 IECC with amendments for all 50 states and the District of Columbia. The analysis covers one- and two-family dwelling units, townhouses, and low-rise multifamily residential buildings covered by the residential provisions of the 2018 IECC.

These analyses evaluate the cost-effectiveness of the prescriptive path of the 2018 edition of the International Energy Conservation Code (IECC), relative to the 2015 IECC with amendments for all 50 states and the District of Columbia. The analysis covers one- and two-family dwelling units, townhouses, and low-rise multifamily residential buildings covered by the residential provisions of the 2018 IECC.

These analyses evaluate the cost-effectiveness of the prescriptive path of the 2018 edition of the International Energy Conservation Code (IECC), relative to the 2015 IECC with amendments for all 50 states and the District of Columbia. The analysis covers one- and two-family dwelling units, townhouses, and low-rise multifamily residential buildings covered by the residential provisions of the 2018 IECC.

These analyses evaluate the cost-effectiveness of the prescriptive path of the 2018 edition of the International Energy Conservation Code (IECC), relative to the 2015 IECC with amendments for all 50 states and the District of Columbia. The analysis covers one- and two-family dwelling units, townhouses, and low-rise multifamily residential buildings covered by the residential provisions of the 2018 IECC.

These analyses evaluate the cost-effectiveness of the prescriptive path of the 2018 edition of the International Energy Conservation Code (IECC), relative to the 2015 IECC with amendments for all 50 states and the District of Columbia. The analysis covers one- and two-family dwelling units, townhouses, and low-rise multifamily residential buildings covered by the residential provisions of the 2018 IECC.

These analyses evaluate the cost-effectiveness of the prescriptive path of the 2018 edition of the International Energy Conservation Code (IECC), relative to the 2015 IECC with amendments for all 50 states and the District of Columbia. The analysis covers one- and two-family dwelling units, townhouses, and low-rise multifamily residential buildings covered by the residential provisions of the 2018 IECC.

These analyses evaluate the cost-effectiveness of the prescriptive path of the 2018 edition of the International Energy Conservation Code (IECC), relative to the 2015 IECC with amendments for all 50 states and the District of Columbia. The analysis covers one- and two-family dwelling units, townhouses, and low-rise multifamily residential buildings covered by the residential provisions of the 2018 IECC.

These analyses evaluate the cost-effectiveness of the prescriptive path of the 2018 edition of the International Energy Conservation Code (IECC), relative to the 2015 IECC with amendments for all 50 states and the District of Columbia. The analysis covers one- and two-family dwelling units, townhouses, and low-rise multifamily residential buildings covered by the residential provisions of the 2018 IECC.

These analyses evaluate the cost-effectiveness of the prescriptive path of the 2018 edition of the International Energy Conservation Code (IECC), relative to the 2015 IECC with amendments for all 50 states and the District of Columbia. The analysis covers one- and two-family dwelling units, townhouses, and low-rise multifamily residential buildings covered by the residential provisions of the 2018 IECC.

These analyses evaluate the cost-effectiveness of the prescriptive path of the 2018 edition of the International Energy Conservation Code (IECC), relative to the 2015 IECC with amendments for all 50 states and the District of Columbia. The analysis covers one- and two-family dwelling units, townhouses, and low-rise multifamily residential buildings covered by the residential provisions of the 2018 IECC.

These analyses evaluate the cost-effectiveness of the prescriptive path of the 2018 edition of the International Energy Conservation Code (IECC), relative to the 2015 IECC with amendments for all 50 states and the District of Columbia. The analysis covers one- and two-family dwelling units, townhouses, and low-rise multifamily residential buildings covered by the residential provisions of the 2018 IECC.

These analyses evaluate the cost-effectiveness of the prescriptive path of the 2018 edition of the International Energy Conservation Code (IECC), relative to the 2015 IECC with amendments for all 50 states and the District of Columbia. The analysis covers one- and two-family dwelling units, townhouses, and low-rise multifamily residential buildings covered by the residential provisions of the 2018 IECC.