Colorado Building Code: Which Editions Are Adopted

Direct answer

No statewide building code; local jurisdictions adopt, with a state-mandated energy-code floor in Colorado. State law requires any local jurisdiction updating a building code after 1 July 2026 to adopt the Colorado Model Low Energy and Carbon Code, based on the 2024 IECC, or a more stringent code. Between 1 July 2023 and 30 June 2026, jurisdictions updating any building code had to adopt the 2021 or 2024 IECC with the Colorado Model Electric Ready and Solar Ready Code. From 1 July 2026 the trigger requires the Model Low Energy and Carbon Code (published 2 September 2025), which absorbs the electric-ready and solar-ready provisions. This was checked on 2026-10-01 against Colorado Energy Office, which is the source that controls. The cross-state comparison further down this page comes from the ICC adoption chart dated January 2024, so where the two disagree the record above is the newer one.

Content and cited inputs reviewed by Harth team · Published 2026-09-07 · Updated 2026-10-01.

Which codes has Colorado adopted now?

No statewide building code; local jurisdictions adopt, with a state-mandated energy-code floor.

State law requires any local jurisdiction updating a building code after 1 July 2026 to adopt the Colorado Model Low Energy and Carbon Code, based on the 2024 IECC, or a more stringent code.

Transition: Between 1 July 2023 and 30 June 2026, jurisdictions updating any building code had to adopt the 2021 or 2024 IECC with the Colorado Model Electric Ready and Solar Ready Code. From 1 July 2026 the trigger requires the Model Low Energy and Carbon Code (published 2 September 2025), which absorbs the electric-ready and solar-ready provisions.

Local adoption: Building code adoption sits with municipalities and counties. There is no single statewide edition, so the permit jurisdiction for the address decides. State agencies set codes only for the buildings they oversee: the Office of the State Architect for state-owned buildings, and the Division of Fire Prevention and Control for public schools, health facilities and limited-gaming buildings.

Checked 2026-10-01 against Colorado Energy Office. Confirm the edition and effective date for the specific permit jurisdiction before relying on it.

The cross-state record

For comparison across states, every I-Code the ICC Master I-Code Adoption Chart (January 2024) tracks, as it records Colorado. Where this disagrees with the record above, the record above is newer:

Colorado has a recorded edition year for 2 of the 17 codes: 2021 for the plumbing and fuel gas codes. The building, residential, fire, mechanical, private sewage, green construction, residential energy, commercial energy, property maintenance, existing buildings, swimming pool and spa, performance, wildland-urban interface, zoning and green building standard codes appear as adopted by individual state or local agencies rather than as a statewide standard, so whether they apply depends on the permit jurisdiction for the project address.

Source: ICC Master I-Code Adoption Chart (January 2024).

How Colorado compares with its neighbours

Statewide editions in force, checked 2026-10-01; “Local” means no state adoption, “(limited)” a state adoption for some buildings only, and * a state-titled code built on that edition.

Utah, Nebraska and New Mexico differ from Colorado on the building code alone. A practice working across that border is working to two editions, whatever the office standard says.

Where Colorado sits in the national record

Colorado is one of 17 jurisdictions with no statewide IBC edition in force. Adoption runs through local programmes or applies only to a subset of buildings, so there is no single answer for the state and the permit jurisdiction for the address decides.

Colorado is one of 15 jurisdictions with no statewide residential energy code based on an IECC edition in force, so the energy question is answered by the state's own document or by the local jurisdiction.

Across all 17 codes the January 2024 ICC chart tracks, Colorado has a recorded edition for 2, which ranked it 46th of 51. A low count is not a gap in regulation — it usually means the state legislates through its own documents, or leaves the discipline to local adoption.

What the chart does and does not tell you

The chart's own legend matters more than the numbers:

• An edition year means one or more state or local agencies adopted that edition. It does not mean every building in the state is designed to it.
• “Some jurisdictions only” is the chart's X: the code is in use somewhere in the state but is not the standard for all buildings.
• “Not adopted” is a blank cell — no state or local jurisdiction reported adopting that code.
• “State-written code” means the state publishes its own document in place of the model edition, so the model text is a reference, not the law.

ICC states plainly that not every jurisdiction notifies it of an adoption, and this chart is dated January 2024. Treat it as the starting point for a search, never as the answer.

How to confirm the edition that governs a Colorado project

1. Open Colorado Energy Office and find the currently adopted code list with its effective date.
2. Check whether the permit authority for the project address is the state or a local programme with its own adoption.
3. Read the state amendments alongside the model edition — an amended table or definition changes the requirement even when the edition matches.
4. Record the permit application date. A code change usually applies from an effective date, and applications filed before it are normally reviewed under the previous edition.
5. Get the answer in writing from the authority having jurisdiction before it drives a design decision.

Colorado code-basis worksheet

Fill this in once per project and keep it with the drawing set. Every row is a question a plan reviewer can ask, and the answer changes with the address and the application date, not with the state.

This worksheet records a determination; it does not make one. The authority having jurisdiction decides which edition and which amendments apply.

Where can you explore related guidance?

• Explore all code adoption guidance
• Utah Building Code: Which Editions Are Adopted
• Wyoming Building Code: Which Editions Are Adopted
• Nebraska Building Code: Which Editions Are Adopted
• New Mexico Building Code: Which Editions Are Adopted

Sources and method

Adopted editions transcribed from the ICC Master I-Code Adoption Chart (January 2024), reproduced with the chart's own legend so an “X” is not mistaken for a statewide adoption. ICC notes that not all jurisdictions report their adoptions and publishes updates at iccsafe.org/adoptions. The current edition, its effective date and the state amendments are published by Colorado Energy Office, which controls.

Source links

• iccsafe.org

• iccsafe.org

• energyoffice.colorado.gov