Roofing in Seattle, WA
Replacing an asphalt roof on a typical Seattle house costs $15,000 to $32,000, a little above the regional average because steep pitches, dormers, narrow side yards and multiple roof sections are common. Many Seattle houses also have at least one low-slope section — a dormer, porch, rear addition or flat-roofed mid-century wing — that needs a membrane rather than shingles.
Seattle roof replacement costs
| Roof | Typical Seattle range | Seattle-specific factors |
|---|---|---|
| Architectural asphalt, simple roof | $15,000 – $24,000 | Bungalows and ramblers with one or two planes |
| Architectural asphalt, steep or cut-up roof | $22,000 – $32,000 | Tudors and Craftsman with dormers and valleys |
| Low-slope membrane section | $8 – $16 per sq ft | Rear additions, porch roofs, mid-century flat roofs |
| Standing-seam metal | $32,000 – $62,000 | Popular on modern infill and solar-ready roofs |
| Cedar shake | $36,000 – $66,000 | Period houses keeping the original look |
Tear-off on older Seattle houses often finds skip sheathing — boards spaced apart for the original cedar shingles — which must be covered with plywood before new shingles go on, adding a few thousand dollars.
Seattle houses and their roofs
Craftsman and bungalow houses have moderate-to-steep pitches, deep eaves with exposed rafter tails, and dormers whose low-slope roofs are a common leak source. Flashing where dormer walls meet the main roof deserves as much attention as the shingles.
Tudors have the steepest roofs in the city, with valleys, chimneys and complicated intersections. They take longer to roof and need roofers comfortable with steep work and proper fall protection.
Mid-century houses in northeast and southeast Seattle often have low-slope or nearly flat roofs, sometimes built-up tar and gravel. Replacing them is a chance to add insulation above the deck, which falls under the energy code.
Infill townhouses often have roof decks and parapets, where membrane, drains and deck supports must be detailed together.
Seattle roofing permits and rules
SDCI's rules on reroofing depend on what is replaced. Work limited to the roof covering is treated differently from work that replaces structural sheathing, adds insulation that changes the roof assembly, or alters roof framing. Ask your roofer what permit, if any, they will pull and why. Houses in historic districts may need review before switching roofing material, such as cedar to asphalt or asphalt to metal.
Older roofing materials and roof-related products can contain asbestos; the Puget Sound Clean Air Agency requires an asbestos survey before many renovation projects in Seattle.
Trees, moss and access in Seattle
Big street and yard trees keep many Seattle roofs in shade for most of the year, which is why moss is the city's most common roof complaint. Trimming overhanging limbs may need a tree arborist and, for large trees, compliance with the city's tree protection rules. Narrow side yards and parked cars on the street complicate debris removal; ask how the roofer will stage dumpsters or trailers and whether a street-use permit is needed.
Seattle roofing questions
My house has skip sheathing. Do I have to replace it?
It usually stays, covered by new plywood or OSB, which gives asphalt shingles the solid deck they need.
Can I put metal on a Craftsman house?
Yes, in most of the city. In historic districts, expect a review. Dark standing-seam metal on a bungalow can look intentional if trim and gutters are detailed to match.
How do I treat moss without damaging the roof?
Use a moss treatment that lets dead moss wash off over time, and trim branches to let light in. Do not pressure wash.
What should I ask about my low-slope dormer?
What membrane they use, how it ties into the shingled roof and the dormer walls, and whether they will add tapered insulation to stop ponding.