Colorado Energy Office Publishes an Updated Building Energy Code

On September 2, 2025, the Colorado Energy Office announced that the Colorado Energy Code Board has published its Model Low Energy and Carbon Code. The code will become Colorado's new minimum energy code on July 1, 2026 for both commercial and residential buildings. Any municipality or county that updates any of its building codes after that date must adopt the Model Low Energy and Carbon Code, or a code that will achieve greater energy efficiency and pollution reductions.

"By focusing on affordable pathways to reduce energy use and greenhouse gas pollution, this code is a smart step forward in Colorado's work to decarbonize the building sector without putting excessive burdens on developers and design teams," said CEO Executive Director Will Toor.

The code is based on a modified version of the 2024 version of the International Energy Conservation Code (IECC), updating the state requirement from the previous 2021 IECC version. The Model Low Energy and Carbon Code includes increased energy efficiency requirements for very large homes, requires certain mechanical systems to be demand response capable, and debiases the code to, for the first time, fairly credit energy savings from high-efficiency electric heating and water heating. Both all electric and mixed fuel buildings will have viable pathways to code compliance.

The Colorado Energy Code Board is a joint initiative between the Colorado Energy Office (CEO) and the Department of Local Affairs (DOLA).

For more information, please view the press release here.