Free roof inspection with deck photos before we talk money - GAF and Owens Corning certified installation
Before
After
Before
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Before
AfterFast, Reliable Roof Installation Across Sebastopol
Roof installation in Sebastopol costs between $11,000 and $28,000 for a typical single-family home, depending on material and the condition of what lies underneath. The fog that rolls through the Petaluma Gap is the real decision-maker here, not the rain itself. It keeps roof decks damp for weeks at a time, which means the roof you install has to be specified for biological control first and storm wear second. Our crews know Sebastopol’s microclimates: the canopy-heavy lots off Bodega Highway, the wetland-adjacent streets near the Laguna, and the older farmhouse stock around Pleasant Hill. Call (743) 200-8347 and we’ll send someone who knows which end of town you’re on before they even pull up.
Why Mercer Roofing Is Sebastopol’s Preferred Roof Installation Company
Sebastopol homeowners keep calling us back because we do one thing most roofers won’t: we tell you exactly who is coming to your door before they arrive. Every technician’s name and photo is sent ahead of the visit, and they badge in with photo ID. If you’ve ever hesitated to open the door to a stranger, that detail matters. It’s the Threshold Verified standard every Mercer location operates under, and it’s not optional.
Our Sebastopol reviews mention the written price most often. You get a line-item quote before any work starts, and that quote is what you pay. No change orders, no discovery-day surprises. We install GAF roof systems almost exclusively in Sebastopol because their synthetic underlayments hold up to the fog belt better than felt, but we also work with CertainTeed, Owens Corning, Atlas, Tamko, and Boral when a homeowner has a specific preference. Every project includes the 365-Day Done Right Promise: if the work isn’t right within a year, we come back and make it right. Written guarantee included. Free second visit if a repair fails.
Grant Whitlock leads our Sebastopol roofing team, and he’s walked more bungalow roofs off Florence Avenue than he can count. That kind of local familiarity means we don’t guess at what a 90-year-old Craftsman needs. We’ve already seen it. Twenty times.
TPO Roofing Installation in Sebastopol
TPO Roofing Installation in Sebastopol runs $9 – $14 per square foot installed, and it’s the right call for low-slope sections, flat garage roofs, and the detached studio spaces and agricultural outbuildings that pepper the older parcels around town. TPO is a heat-welded single-ply membrane that reflects heat well, but the reason we recommend it here is weld strength. In a fog belt where every seam stays damp for weeks, a properly welded TPO seam won’t delaminate the way older adhesive-style membranes do.
When TPO Makes Sense on an Old Sebastopol Property
Many of the original barns and carriage houses from the orchard era have roof pitches too shallow for shingles. TPO handles a 1/4:12 slope without ponding issues, and the white or light-gray membrane reduces heat gain in those uninsulated outbuildings. If your detached structure still has its original low-slope roof, expect the decking replacement conversation to come up. We rarely strip an old barn roof in Sebastopol without finding rot at the eave edges where fog drips all winter.
What We Specify Under and Over the Membrane
We use a high-density cover board under TPO on any deck that shows moisture history, and on every Sebastopol TPO install we specify stainless fasteners at the perimeter and penetration points. Standard electroplated fasteners are the cheapest part of the job and the first to fail in Petaluma Gap marine air. The copper-colored oxidized TPO blends well with the agricultural look, and a white membrane keeps the upper-floor temperature down in those late-August heat spikes.
Shingle Roof in Sebastopol
Shingle Roof installation in Sebastopol runs $11,000 – $26,000 for a full tear-off and replacement on a typical 1,200 – 2,200 square foot home. The spread is wide because what’s hiding under the shingles varies wildly in this town. A 1950s ranch on a sunny Cotati-adjacent lot might need only new underlayment and shingles. A 1910 Craftsman under redwood canopy off Gravenstein Highway will likely need decking repair, new fascia, and a moss-control strategy built into the roof itself.
Architectural Shingles on Older Homes
We install GAF Timberline HDZ architectural shingles as our default spec in Sebastopol because the dimensional profile hides the subtle waviness of old framing better than a flat three-tab, and the nail-strip design holds better in the wind gusts that come through the gap. For homeowners matching a historic profile, CertainTeed Presidential Shake gives the heavy shadow line of original wood shake without the rot liability. We’ll match the existing architectural style, not just the color.
Underlayment and Ventilation for the Fog Belt
We use synthetic moisture-resistant underlayment on every Sebastopol shingle roof, never felt. The fog keeps felt soggy for weeks, and soggy felt rots decking from the underside. We also inspect and usually upgrade attic ventilation on older bungalows, because a damp roof deck that can’t dry between fog cycles fails structurally within a decade. If you live near the Laguna, proper ridge and soffit venting isn’t optional.
Trusted Brands We Service in Sebastopol
We install GAF shingles more than any other brand in this town for a simple reason: their synthetic underlayment line and HDZ nail-strip shingles perform in prolonged damp conditions better than anything else we’ve stripped and compared. When homeowners want a specific look or a matching historic profile, we work with CertainTeed, Owens Corning, Atlas, Tamko, and Boral as well. Our crews keep common GAF match components on the truck for Sebastopol jobs: ridge caps, vent boots, and drip edge in the browns and grays this town favors. That means fewer trips back to Santa Rosa and a faster start when your tear-off reveals something no one expected.
Common Roof Installation Problems We See in Sebastopol Homes
- Underside rot on original wood shake. When we strip a 1920s Craftsman in Sebastopol, the north-facing decking is often so damp it needs sistered framing before we can lay new sheathing. The fog here doesn’t just wet the surface; it keeps moisture inside the roof assembly for weeks, and old shake roofs have no ventilation to release it.
- Moss re-colonization within two to three years. North- and west-facing slopes near the Laguna de Santa Rosa or under apple canopy rarely dry fully between fog cycles. Moss comes back fast enough that we now recommend zinc or copper ridge strips as a standard line item on those elevations, not an add-on you have to ask for.
- Corroded fasteners and flashing. Standard electroplated nails and thin-gauge steel flashing fail early in Petaluma Gap marine air. We specify hot-dip galvanized or stainless fasteners and sealed flashing joints on every Sebastopol install, because the roof fails at the penetrations first.
- Decking surprises on old orchard properties. Sebastopol’s original homestead lots often have additions and outbuildings roofed decades apart with different materials, and the transitions leak. When we open those up, the cost change is real. That’s why our written quote includes a decking replacement allowance stated up front, so you know the worst-case number before we start.
Pricing for Roof Installation in Sebastopol, CA
A full shingle roof installation in Sebastopol runs $11,000 – $26,000. TPO on a flat or low-slope section runs $9 – $14 per square foot. The variables are the decking condition, the number of elevations that need copper or zinc ridge strips, and whether the home has original wood shake that requires full tear-off and re-sheathing. A coastal-spec roof with hot-dip fasteners, synthetic underlayment, and marine-grade flashing runs about 12 – 18% more than the inland-spec version of the same job using electroplated nails and felt. But the inland-spec roof in this fog belt is the one that needs a $4,000 – $8,000 decking repair within a decade. We write every quote as a fixed line-item price before work begins, and the estimate is free. Call (743) 200-8347 to schedule one.
We Also Serve Cities Near Sebastopol
Our crews cover Sebastopol and the surrounding Sonoma County communities, including Roof Installation work in Santa Rosa, Rohnert Park, Cotati, and Windsor. Each of those towns has its own climate patterns and housing stock, and we spec the materials accordingly. For more on how we approach roofs across the county, see our Sebastopol service page. Whether you’re in a 1905 farmhouse near downtown or a 1980s ranch in a newer subdivision, the written-price promise applies the same.
Serving Sebastopol, CA - Our Local Coverage Area
We’re based in the Sebastopol area and know this community well. Use the map below to see our service coverage - if you’re nearby, we can almost certainly help.
FAQs About Roof Installation in Sebastopol
The fog and shade mean we specify hot-dip galvanized or stainless fasteners, synthetic underlayment, and usually architectural shingles on every job. Standard electroplated nails corrode in the marine air within a few years, and felt underlayment stays wet for weeks. Those two substitutions add roughly 12 – 18% to material cost but double or triple the effective life of the roof in this climate. Call (743) 200-8347 and we’ll write the exact numbers for your home.
Because moss re-colonizes north- and west-facing slopes within two to three years of a new install in this town, especially near the Laguna de Santa Rosa or under redwood and apple canopy. When rain hits zinc or copper ridge strips, it carries trace metal ions down the shingle surface that suppress moss regrowth. They add a few hundred dollars to the job and save a pressure-wash cycle every other year. Well worth it on shaded elevations.
Almost never. Wood shake roofs can’t be re-shingled directly because the uneven shake surface telegraphs through new shingles, and the old shake layer traps moisture. Worse, in Sebastopol the shake is usually rotted from the underside already, which means the decking beneath it needs inspection and often replacement. We’ll strip it, assess the decking, and quote the full picture before any work starts. Call (743) 200-8347 for a free estimate on your bungalow.
A coastal-spec roof using hot-dip galvanized fasteners, synthetic underlayment, and sealed flashing joints runs about 12 – 18% more than the inland-spec version of the same job, which might add $2,000 – $4,000 to a 1,800-square-foot roof. But the cheap spec in Sebastopol’s fog belt typically fails at the fasteners and flashing within eight to ten years, and the resulting decking repair costs more than the original savings. The coastal spec is actually the cheaper roof over any timeframe longer than a decade.
We treat moss at the source during the install: copper or zinc ridge strips on shaded slopes, moss-inhibiting shingle granules where available, and a ventilation upgrade so the deck actually dries between fog cycles. After installation, no pressure washing, ever. Pressure washing strips the granule surface off shingles and shortens their life. If moss appears later, the 365-Day Done Right Promise covers our work, and we’ll advise on the right maintenance chemistry for your specific exposure. Call (743) 200-8347 to talk it through.
Written by Grant Whitlock, Owner at Mercer Roofing, serving Sebastopol, CA and Sonoma County.