Denver enforces the 2025 Denver Building and Fire Code, which is based on the 2024 I-codes, and you need a permit once a roof repair passes 10% of the roof or two squares, whichever is smaller. An ice barrier is not required, and a roof with two or more layers must be torn off to the deck.
General information, read from the official sources listed below on 2026-10-28. Codes and local policies change, so confirm the rules for your address with the building department before work starts.
Denver roof code data table
| Item | Denver |
|---|---|
| Adopted IRC edition | 2025 Denver Building and Fire Code, based on the 2024 I-codes. The city page does not name the IRC edition separately. Source: Denver Building Codes, Policies and Guides |
| Adopted IBC edition | 2025 Denver Building Code, based on the 2024 IBC. The energy code incorporates the 2021 IECC. Source: Denver Building Codes, Policies and Guides |
| Adoption or effective date | Adopted June 13, 2025; 2nd printing adopted November 24, 2025. The city page gives the effective date as December 31 without a year. Source: Denver Building Codes, Policies and Guides |
| Roofing amendments and local policies | Roofing Guide (updated 4/11/2024, before the 2025 code): no continuous opening between boards over 1/2 in; for asphalt, no opening over 6 sq in, with smaller ones covered by 26-gauge metal; shingles labeled to ASTM D7158, or D3161 if outside D7158 scope; exposed uninsulated cavities insulated to R-30ci above or R-38 flat / R-49 attic below the sheathing; coatings need no permit. Source: Denver Roofing Guide and Checklist (updated 4/11/2024) |
| Ice barrier rule | Not required (Denver Table R301.2: No). Source: Denver Roofing Guide and Checklist (updated 4/11/2024) |
| Ground snow load | 35 psf ground snow load. Source: Denver Roofing Guide and Checklist (updated 4/11/2024) |
| Design wind speed | Minimum shingle rating by zone: 115 mph east of Federal Blvd., 125 mph from Federal to Sheridan, 140 mph from Sheridan to Kipling. Source: Denver Roofing Guide and Checklist (updated 4/11/2024) |
| Reroof permit trigger | Repairs over 10% of the roof or two squares, whichever is smaller (5% for buildings of 25,000 sq ft or more). Every new penetration needs a permit. Partial roofs may be replaced only to a natural edge, not partial slopes. Source: Denver Roofing Guide and Checklist (updated 4/11/2024) |
| Layers allowed | Where two or more layers of any covering exist, the roof must be removed to the deck. Over a single layer, the IRC recover limits apply. Source: Denver Roofing Guide and Checklist (updated 4/11/2024) |
| Wildfire / WUI code status | Not fully verified: Not stated in the sources read for this page. Ask the building department. |
| Inspection requirements | One- and two-family asphalt reroofs: no pre-inspection (205), mid-roof (206) only if needed, final roof inspection (201) required. Tile and metal: mid-roof and final. Attic venting is not inspected on reroofs. Source: Denver Roofing Guide and Checklist (updated 4/11/2024) |
| Permitting office | Denver Community Planning and Development, building codes and permits. Source: Denver Building Codes, Policies and Guides |
What it means for a homeowner reroofing in Denver
Denver measures a repair against the whole roof. On a 25-square house, 10% is 2.5 squares, so the two-square cap is the smaller number and decides it: replacing more than 200 square feet of shingles needs a permit. Replacing whole roof planes is allowed under a permit only if the new roofing stops at a natural edge, never mid-slope.
Your street address sets the wind rating your shingles must carry. A bungalow east of Federal Boulevard needs a 115 mph minimum rating, while a home between Sheridan and Kipling needs 140 mph. Ask the roofer which zone the quote assumes.
Denver is one of the few Front Range jurisdictions that does not require an ice barrier, and it does not inspect attic venting on a reroof. If the old roof had no insulation in the rafter cavity and the sheathing gets exposed, though, the energy rule forces insulation, which is a real cost on older flat and low-slope roofs.
Common inspection failures in Denver
These are items the building department's own code or handouts say it checks or rejects. No public data ranks how often each one fails, so the order means nothing.
- Repair grew past two squares without a permit.
- A partial reroof ended mid-slope instead of at a natural edge.
- Shingle wrapper lacks the ASTM D7158 (or D3161) wind label for the zone.
- Board gaps over 1/2 in, or asphalt-roof openings over 6 sq in, left uncovered.
- A new skylight, pipe or solar penetration added without a permit.
- Exposed uninsulated cavity closed up without the required insulation.
- No proof of the asbestos inspection CDPHE rules require.
Steps to permit a reroof in Denver
- Measure the work against 10% of the roof and two squares to see if a permit is needed.
- Find the wind zone (Federal, Sheridan, Kipling) and confirm the shingle label matches.
- Check whether the roof has two or more layers; if so, plan a full tear-off.
- List any new penetrations so they go on the permit.
- Book the final roof inspection (code 201) when the job is done.
Related pages
- Denver roofing
- Denver roofing codes explained
- Colorado Wildfire Resiliency Code on a reroof
- Roof replacement
- Roof repair
- Hail damage repair
- Free roof inspection
- Compare roof codes by jurisdiction
Hail history by ZIP in Denver: 80220 (Denver), 80238 (Denver)
Sources
Compiled by Integrity Roofing and Painting, roofing Colorado homes since 1990 (36 years in business). We are an Owens Corning Platinum Preferred contractor with 650+ Google reviews, and our repair scopes follow the local code and the manufacturer's installation and warranty requirements. We do not issue permits or rule on code; the building department does.
