No, Denver roofs do not need ice and water shield at the eaves by code; the City and County of Denver’s roofing checklist says so directly. Some neighbors do: Centennial requires an ice barrier on all roofs, and Littleton requires one at the eaves extending two feet inside the exterior wall. We install it on Denver roofs anyway at the eaves, in valleys, along walls and around chimneys and skylights, because those are the spots where melting snow backs up and leaks.
What the codes say in the Denver area
| Jurisdiction | Ice barrier at the eaves | Source |
|---|---|---|
| City and County of Denver | Not required | Roofing Guide and Checklist, updated 4/11/2024 |
| Centennial | Required on all roofs | Residential Roof Repairs and Re-Roofing page |
| Littleton | Required: ASTM D1970 membrane at eaves of all conditioned structures, at least 2 feet inside the exterior wall | Policy 24-001, 5th revision, 5/21/2026 |
Denver still designs roofs for a 35 psf ground snow load, the figure in its own climate table. Snow sits on Denver roofs; whether it causes a leak depends on what is under the shingles at the eaves. For other Denver code points, see Denver roofing codes and our Littleton roof code guide.
How ice dams leak
During the day, heat from the house warms the roof deck and melts the snow above the living space. The water runs down to the cold overhang and the gutter, where it freezes. Night after night the ridge of ice grows, and new meltwater pools behind it. Shingles are built to shed water running downhill, not to hold back a pond, so the water works up under the shingles and into the wall or ceiling. A self-adhering membrane bonded to the deck and sealed around every nail keeps that pond out of the house.
Where we install it on Denver roofs
- Eaves, at least two feet past the warm wall.
- Valleys, under metal or on its own. Valleys carry the most water on the roof.
- Wall abutments, on the deck before step flashing and counterflashing. On a reroof the membrane goes on the roof surface, not up the finished wall.
- Chimneys and skylights, where snow piles up on the uphill side.
- Low slopes, where water drains slowly; Denver requires double underlayment from 2:12 up to 4:12, and a full membrane is often better.
These locations are part of the Integrity Roofing System. For the product itself, how it compares to felt and synthetic underlayment, and how it behaves in cold weather, read self-adhering underlayment explained.
Fix the cause, not just the leak
Ice and water shield is the last line of defense. To keep ice dams from forming:
- seal attic air leaks around lights, fans and the attic hatch;
- bring attic insulation up to current levels; Denver’s checklist requires insulation when a reroof exposes an uninsulated roof cavity;
- balance intake vents at the soffits with exhaust at the ridge. Denver does not inspect venting on reroofs, but it can be added to meet the shingle manufacturer’s requirements.
Switching from wood shakes? That changes ventilation and flashing too; see replacing wood shingles with asphalt in Denver. Planning a winter project? See installing roofs year-round in Colorado.
Ask your roofer three questions
- Will you install ice and water shield at the eaves, and how far past the wall line?
- Will it go in every valley and along every wall and chimney?
- Which product, and is it a self-adhering membrane meeting ASTM D1970?
Integrity Roofing and Painting is family-run since 1990, veteran-owned, and an Owens Corning Platinum Preferred contractor with 650+ Google reviews. Our Denver-area office is at 13275 E. Fremont Pl in Centennial. Call (303) 209-0152, book a free Denver roof inspection, or see Denver roof replacement.
Sources: City and County of Denver, Roofing Guide and Checklist (updated 4/11/2024); City of Centennial, Residential Roof Repairs and Re-Roofing; City of Littleton, Policy 24-001 (5th revision, 5/21/2026); Pikes Peak Regional Building Department, Reroofing Guidelines (rev. 03/05/2024).
