Energy Codes

Codes and Standards
Contact: Vladimir Kochkin
[email protected]
Director, Codes & Standards
(202) 266-8574

Energy codes are national model building codes that set minimum energy efficiency standards for many components in a new home, like lights, climate systems, insulation, windows, and more. The two most widely adopted energy codes are the International Energy Conservation Code (IECC) for single-family homes and ASHRAE’s Energy Standard for Buildings Except Low-Rise Residential Buildings (ASHRAE 90.1) for multifamily properties.

After an energy code is published once every three years, the Department of Energy compares the latest edition of the code to the previous edition to determine if the code has become more energy efficient. A positive by DOE triggers a series of requirements that are outlined in the DOE Determinations State Certifications Fact Sheet.

When a state or jurisdiction goes through the adoption process for an energy code, there are typically public hearings and an opportunity to amend the code prior to adoption. NAHB has developed a series of adoption kits that include highlights of changes from the previous code, associated cost increases and a list of suggested amendments.

Energy Code Adoption Cost Analysis

These cost studies quantify the economic impact of adopting specific energy codes and include the methodology used.

Energy Code Adoption by State

Most states adopt a statewide energy code that is an amended version of a national model code. This Adoption Summary Spreadsheet lists the current energy code in place for each state and describes the key amendments that were made to the model code along with a link to the amended version of the code. See the map below for a quick overview of IECC adoption status by state.

For more on the current IECC adoption cycle, see NAHB’s 2021 IECC Code Adoption Kit.


2024 IECC Development Process
2021 IECC Adoption Toolkit