Updated 2026-09-07

US Building Code Adoption by State

Colorado Building Code: Which Editions Are Adopted

Which I-Code editions Colorado is recorded as adopting, what the record does not cover, and how to confirm the edition governing a project.

On this page

Last updated September 7, 2026 · Adopted editions transcribed from the [ICC Master I-Code Adoption Chart (January 2024)](https://www.iccsafe.org/wp-content/uploads/Master-I-Code-Adoption-Chart-1.pdf), 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](https://www.iccsafe.org/adoptions). The current edition, its effective date and the state amendments are published by [Colorado's official building-code publication](https://osa.colorado.gov/state-buildings/building-codes), which controls.

Direct answer

No statewide building code; local jurisdictions adopt, with a state-mandated energy-code floor in Colorado. State law requires a local jurisdiction updating any building code to adopt and enforce the 2021 IECC together with the Colorado Model Electric Ready and Solar Ready Code. Building code adoption sits with municipalities and counties. There is no single statewide edition, so the permit jurisdiction for the address decides. This was checked on 2026-09-08 against Colorado Energy Office, which is the source that controls. Record the permit application date with it: a code change normally applies from an effective date, and an application filed before that date is usually reviewed under the previous edition. 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 Scott Barrington, Harth founder and architectural technology specialist · Published 2026-09-07 · Updated 2026-09-07.

Code-adoption status diagram: Colorado Building Code: Which Editions Are Adopted
Which I-Code editions Colorado is recorded as adopting, what the record does not cover, and how to confirm the edition governing a project.

What must be verified before using this guidance?

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

State law requires a local jurisdiction updating any building code to adopt and enforce the 2021 IECC together with the Colorado Model Electric Ready and Solar Ready Code.

DisciplineAdopted
Energy2021 IECC plus the Model Electric Ready and Solar Ready Code, triggered on any code update
Building and residentialLocal adoption; no statewide edition

Local adoption: Building code adoption sits with municipalities and counties. There is no single statewide edition, so the permit jurisdiction for the address decides.

Checked 2026-09-08 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:

CodeRecorded adoption
International Building Code (IBC)Some jurisdictions only
International Residential Code (IRC)Some jurisdictions only
International Fire Code (IFC)Some jurisdictions only
International Mechanical Code (IMC)Some jurisdictions only
International Plumbing Code (IPC)2021
International Private Sewage Disposal Code (IPSDC)Some jurisdictions only
International Fuel Gas Code (IFGC)2021
International Green Construction Code (IgCC)Some jurisdictions only
International Energy Conservation Code — Residential (IECC-R)Some jurisdictions only
International Energy Conservation Code — Commercial (IECC-C)Some jurisdictions only
International Property Maintenance Code (IPMC)Some jurisdictions only
International Existing Building Code (IEBC)Some jurisdictions only
International Swimming Pool and Spa Code (ISPSC)Some jurisdictions only
ICC Performance Code (ICCPC)Some jurisdictions only
International Wildland-Urban Interface Code (IWUIC)Some jurisdictions only
International Zoning Code (IZC)Some jurisdictions only
ICC 700 National Green Building Standard (ICC 700)Some jurisdictions only

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

StateBuilding (IBC)Residential (IRC)Residential energy (IECC-R)
ColoradoSome jurisdictions onlySome jurisdictions onlySome jurisdictions only
Utah202120212015
Wyoming2021Some jurisdictions onlySome jurisdictions only
Nebraska201820182018
New Mexico201520152018

Utah, Wyoming, 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 7 jurisdictions with no statewide IBC edition in this record. Adoption runs through individual state agencies or local programmes instead, so there is no single answer for the state and the permit jurisdiction for the address decides.

Across all 17 codes the chart tracks, Colorado has a recorded edition for 2, which ranks 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's official building-code publication 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.

ItemProject entry
Project address and permit jurisdiction
State programme or local programme as AHJ
Building / residential edition and effective date
Energy code edition (or state-written code)
Fire, mechanical, plumbing and fuel-gas editions
Accessibility standard and edition
State amendments consulted (citation)
Local amendments consulted (citation)
Permit application date and vesting rule
Written AHJ confirmation (date, name)

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

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's official building-code publication, which controls.

Frequently asked questions

Which building code edition does Colorado use?

The ICC Master I-Code Adoption Chart (January 2024) does not record a single statewide IBC edition for Colorado. Adoption there runs through individual state or local agencies, so the governing edition depends on the permit jurisdiction for the project address rather than on a statewide rule.

Why does this page not simply state today's code?

Because the underlying record is dated. The ICC Master I-Code Adoption Chart (January 2024) is the most complete cross-state source available, and ICC notes that not every jurisdiction reports its adoptions. Publishing it with its date attached and sending you to Colorado's official building-code publication is honest; publishing an undated “current edition” would not be.

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