Publications

The International Energy Conservation Code (IECC) prototype building models (prototype models) were developed by Pacific Northwest National Laboratory (PNNL), in support of DOE's Building Energy Codes Program (BECP), to simulate energy savings associated with changes in energy codes and standards. For residential buildings, PNNL utilized two base prototypes to simulate both Single-family detached house, and Multi-family low-rise apartment building types. Energy models for the recent versions of the IECC are available for each climate.

This report provides an assessment as to whether new buildings constructed to the commercial energy efficiency provisions of the 2021 IECC would save energy and energy costs as compared to the 2018 IECC. The Commercial Energy Efficiency chapter in the 2021 IECC allows users to either follow the provisions in the IECC or use Standard 90.1-2019 as an alternative compliance path. As such, PNNL also compared the energy performance of the 2021 IECC with the corresponding Standard 90.1-2019 to help states and local jurisdictions make informed decisions regarding model code adoption.

The most recent edition, the 2021 IECC, was published on January 29, 2021, triggering the DOE review and determination process. DOE and Pacific Northwest National Laboratory (PNNL) conducted a technical analysis to determine energy savings for the 2021 IECC residential provisions relative to the previous edition, the 2018 IECC (ICC 2017). This report documents the methodology used to conduct the analysis and summarizes the results.

PNNL evaluated the cost effectiveness of the changes in the prescriptive and mandatory residential provisions of the 2021 edition of the IECC, compared to those in the prior edition, the 2018 IECC.

PNNL evaluated the cost effectiveness of the changes in the prescriptive and mandatory residential provisions of the 2021 edition of the IECC, compared to those in the prior edition, the 2018 IECC.

PNNL evaluated the cost effectiveness of the changes in the prescriptive and mandatory residential provisions of the 2021 edition of the IECC, compared to those in the prior edition, the 2018 IECC.

PNNL evaluated the cost effectiveness of the changes in the prescriptive and mandatory residential provisions of the 2021 edition of the IECC, compared to those in the prior edition, the 2018 IECC.

PNNL evaluated the cost effectiveness of the changes in the prescriptive and mandatory residential provisions of the 2021 edition of the IECC, compared to those in the prior edition, the 2018 IECC.

PNNL evaluated the cost effectiveness of the changes in the prescriptive and mandatory residential provisions of the 2021 edition of the IECC, compared to those in the prior edition, the 2018 IECC.

PNNL evaluated the cost effectiveness of the changes in the prescriptive and mandatory residential provisions of the 2021 edition of the IECC, compared to those in the prior edition, the 2018 IECC.

PNNL evaluated the cost effectiveness of the changes in the prescriptive and mandatory residential provisions of the 2021 edition of the IECC, compared to those in the prior edition, the 2018 IECC.

PNNL evaluated the cost effectiveness of the changes in the prescriptive and mandatory residential provisions of the 2021 edition of the IECC, compared to those in the prior edition, the 2018 IECC.

PNNL evaluated the cost effectiveness of the changes in the prescriptive and mandatory residential provisions of the 2021 edition of the IECC, compared to those in the prior edition, the 2018 IECC.

PNNL evaluated the cost effectiveness of the changes in the prescriptive and mandatory residential provisions of the 2021 edition of the IECC, compared to those in the prior edition, the 2018 IECC.

PNNL evaluated the cost effectiveness of the changes in the prescriptive and mandatory residential provisions of the 2021 edition of the IECC, compared to those in the prior edition, the 2018 IECC.

PNNL evaluated the cost effectiveness of the changes in the prescriptive and mandatory residential provisions of the 2021 edition of the IECC, compared to those in the prior edition, the 2018 IECC.

PNNL evaluated the cost effectiveness of the changes in the prescriptive and mandatory residential provisions of the 2021 edition of the IECC, compared to those in the prior edition, the 2018 IECC.

PNNL evaluated the cost effectiveness of the changes in the prescriptive and mandatory residential provisions of the 2021 edition of the IECC, compared to those in the prior edition, the 2018 IECC.

PNNL evaluated the cost effectiveness of the changes in the prescriptive and mandatory residential provisions of the 2021 edition of the IECC, compared to those in the prior edition, the 2018 IECC.

PNNL evaluated the cost effectiveness of the changes in the prescriptive and mandatory residential provisions of the 2021 edition of the IECC, compared to those in the prior edition, the 2018 IECC.

PNNL evaluated the cost effectiveness of the changes in the prescriptive and mandatory residential provisions of the 2021 edition of the IECC, compared to those in the prior edition, the 2018 IECC.

PNNL evaluated the cost effectiveness of the changes in the prescriptive and mandatory residential provisions of the 2021 edition of the IECC, compared to those in the prior edition, the 2018 IECC.

PNNL evaluated the cost effectiveness of the changes in the prescriptive and mandatory residential provisions of the 2021 edition of the IECC, compared to those in the prior edition, the 2018 IECC.

PNNL evaluated the cost effectiveness of the changes in the prescriptive and mandatory residential provisions of the 2021 edition of the IECC, compared to those in the prior edition, the 2018 IECC.

PNNL evaluated the cost effectiveness of the changes in the prescriptive and mandatory residential provisions of the 2021 edition of the IECC, compared to those in the prior edition, the 2018 IECC.