Littleton Roofing Codes: Permits, Inspections, and Requirements
Adopted building and energy codes, permit rules, and roofing requirements for Littleton, Arapahoe, Douglas and Jefferson Counties. Rows below reflect our reading of the jurisdiction's own published sources, linked at the bottom of the page.
Building department
303-795-3863Inspection line
303-795-3863Permit line
303-795-3863Official department
Live code pageLittleton roofing code requirements
- What this jurisdiction requires
- 2021 IBC and 2021 IRC
- What this jurisdiction requires
- 2021 IECC
- What this jurisdiction requires
- Yes
- What this jurisdiction requires
- Class A
- What this jurisdiction requires
- D 225, D 3462, D 3161, or D 7158
- What this jurisdiction requires
- Yes, with one story access
- What this jurisdiction requires
- Yes, inspection required once all roof covering has been removed and new underlayment has been installed.
- What this jurisdiction requires
- One layer
- What this jurisdiction requires
- One layer
- What this jurisdiction requires
- Required
- What this jurisdiction requires
- Drip edge shall extend a minimum of ¼" below the sheathing and extend up the roof deck a minimum of 2" onto the decking.
- What this jurisdiction requires
- Required
- What this jurisdiction requires
- Ice barrier required at eaves per the IRC
- What this jurisdiction requires
- Two layers of underlayment
- What this jurisdiction requires
- One layer of underlayment
- What this jurisdiction requires
- Closed and Open
- What this jurisdiction requires
- Minimum 24" wide 26-gage galvanized steel
- What this jurisdiction requires
- Required where the roof meets a wall
- What this jurisdiction requires
- No
- What this jurisdiction requires
- Yes
- What this jurisdiction requires
- Required, installed to manufacturer specifications
- What this jurisdiction requires
- Yes
- What this jurisdiction requires
- Required on new construction under the 2021 IECC
- What this jurisdiction requires
- Required per IRC attic ventilation provisions
| Requirement | What this jurisdiction requires |
|---|---|
| Current building code | 2021 IBC and 2021 IRC |
| Current energy code | 2021 IECC |
| Building permit required | Yes |
| Roof system fire rating (residential) | Class A |
| ASTM standard for wind rating | D 225, D 3462, D 3161, or D 7158 |
| Inspectors carry ladders for the final | Yes, with one story access |
| Requires midroof (in progress) inspection | Yes, inspection required once all roof covering has been removed and new underlayment has been installed. |
| Maximum layers of asphalt shingles permitted | One layer |
| Maximum layers of flat roof material permitted | One layer |
| Requires drip edge | Required |
| Minimum drip edge size | Drip edge shall extend a minimum of ¼" below the sheathing and extend up the roof deck a minimum of 2" onto the decking. |
| Requires rake / gable metal edging | Required |
| Self adhering underlayment (ice and water shield) | Ice barrier required at eaves per the IRC |
| Underlayment required 2:12 up to 4:12 | Two layers of underlayment |
| Underlayment required 4:12 and above | One layer of underlayment |
| Type of valleys allowed | Closed and Open |
| Valley material required for open valleys | Minimum 24" wide 26-gage galvanized steel |
| Kick-out required on step flashing | Required where the roof meets a wall |
| Minimum curb height requirement | No |
| Requires positive drainage | Yes |
| Requires ridge cap | Required, installed to manufacturer specifications |
| Requires ventilation to meet code | Yes |
| Blower door test when increasing ventilation to code | Required on new construction under the 2021 IECC |
| Requires soffit / eave vents | Required per IRC attic ventilation provisions |
Last checked September 2, 2026. This reflects published sources at that date, not an official ruling. Code adoptions change, so confirm with the Littleton building department before you pull a permit.
What Littleton requires, in plain language
Littleton builds to the 2021 IBC and 2021 IRC. That edition, not the newest code published nationally, is the rulebook an inspector in Arapahoe, Douglas and Jefferson Counties holds your roof to. Energy work on the same permit follows the 2021 IECC.
Layer limit in Littleton: One layer. This is the line item that moves a bid the most. If your existing roof is already at the limit, the deck gets stripped before new material goes down, and the labor plus dump fees belong in the written price. Flat roof sections are capped at One layer.
Wind is what Littleton tests shingles against. Rating is proven under D 225, D 3462, D 3161, or D 7158.
Underlayment and edge metal are where roofs fail inspection. Ice and water shield: Ice barrier required at eaves per the IRC. On 2:12 to 4:12 slopes: Two layers of underlayment. On 4:12 and steeper: One layer of underlayment. Drip edge: Required. Minimum drip edge size Drip edge shall extend a minimum of ¼" below the sheathing and extend up the roof deck a minimum of 2" onto the decking..
Littleton Ordinance No. 26, Series 2022 adopted the 2021 IBC, IRC, IMC, IPC, IFGC, IECC, IEBC, International Property Maintenance Code and IFC, plus the 2020 NEC.
Installation details above come from our building department field survey for Littleton, last updated 9/9/18. Code editions and contacts are refreshed from the department directly. Always confirm the details on your permit before work starts, since departments amend requirements on their own schedule.
Sources
These links go straight to the jurisdiction, so you always have the real-time source. Adoptions and amendments change on their schedule, not ours. Always confirm before permitting.
Last checked September 2, 2026. This is our best read of published sources, not an official ruling. Confirm with the Littleton building department before you pull a permit.