Photo of a city skyline of office buildings, with an apartment complex in the foreground.

An estimated 75% of U.S. buildings will be new or renovated by 2035. Building energy codes ensure they use energy efficiently over the life of the building.

The Building Technologies Office (BTO) supports the development and implementation of residential and commercial building energy codes by engaging with government and industry stakeholders, and by providing technical assistance for code development, adoption, and compliance. Through advancing building codes, we aim to improve building energy efficiency, and to help states achieve maximum savings. For more information, visit

The Building Energy Codes Program

Building Energy Codes High-Level Overview

Building Energy Codes Fact Sheet

DOE Energy Codes Website