Free roof inspection with deck photos before we talk money - GAF and Owens Corning certified installation
Fast, Reliable Roof Installation Across Sonoma
A full roof installation in Sonoma typically runs $14,500 – $34,000 depending on the material, pitch, and what we find under the existing roof, and most projects take five to ten working days once permits are approved. We work throughout Sonoma Valley, from the historic neighborhoods around the Plaza to the hillside properties off Arnold Drive and Lovall Valley Road, and every job starts the same way: a written price before we touch anything. If you’re weighing a new roof, call (743) 200-8347 for a free estimate. A real person answers.
Why Mercer Roofing Is Sonoma’s Preferred Roof Installation Company
Sonoma homeowners keep calling us for a reason that has little to do with shingle brands. Before a Mercer technician ever steps onto your property, you receive their name and photo. When they ring the bell, they’re wearing a clean uniform and holding a photo ID badge. That’s the Threshold Standard, and it’s the single biggest difference between us and a crew that just shows up. For a homeowner who’s often home alone, or for parents with young kids, that pre-visit photo changes the whole experience.
We’re part of the Threshold Group family, founded in 2000, and each location is independently owned and operated under a quality framework the group enforces contractually. Our lead in this region is Grant Whitlock. He has built the Sonoma operation around one promise: every repair and installation includes a written, 365-day Done Right Promise. If the work isn’t right within a year, we make it right. That’s not a slogan. It’s printed on the paperwork we hand you before the first nail goes in.
Our Roof Installation team also knows what Sonoma inspectors look for, because we’ve stood in front of them on dozens of re-roofing permits across the city. That local permitting fluency, combined with a live person answering the phone 24/7, means you’re never left guessing where your job stands.
Tile Roof in Sonoma
Tile roof replacement in Sonoma runs $22,000 – $45,000 for a typical 2,000 – 3,000 square foot home, with clay and concrete tile driving the higher end and the sheer number of Spanish Colonial Revival and Mission-style homes in Sonoma making this the most common roof type we install. The city’s identity as the site of Mission San Francisco Solano shows up in its architecture: barrel tile profiles, low slopes, and deep eaves that demand careful flashing work.
What a Tile Job Actually Involves Here
We tear off the old tile and battens down to the decking, inspect the framing and sheathing, then install new underlayment before resetting tile. In Sonoma, that underlayment step matters more than almost anywhere else, and we’ll get to why in a moment. The short version: your permit depends on it.
What We Find Under Old Tile
Homes built in the 1960s through 1980s frequently have underlayment that’s cracked or delaminated from years of 100°F summer heat cycling. When we lift old clay tile, we usually find the felt beneath has turned brittle. On the fog-damp north planes, it’s often worse.
Roof Ventilation in Sonoma
Roof ventilation in Sonoma is a frequent add-on during a full install, and if it’s part of the job you’re generally looking at $800 – $3,500 depending on attic configuration, existing intake, and how much ridge vent or box venting the code calculations require. Sonoma’s summer spikes above 95°F bake attics, and without proper ventilation, underlayment degrades faster and air conditioning bills climb.
Ridge and Eave Vent Upgrades
A balanced system pulls air in through soffit or eave vents and exhausts it at the ridge. On older Sonoma homes, we often find eaves blocked by decades of paint or insulation, which means the ridge vent alone won’t move much air. We clear and correct both sides as part of the install.
Ventilation and Tile Roofs
Tile holds heat and releases it slowly, so the attic under a tile roof can stay hot long after sunset. In Sonoma Valley that’s a real comfort and longevity issue. The fix is usually straightforward on the intake side, and we’ll show you the ventilation math in writing before you approve it.
Trusted Brands We Service in Sonoma
We install and repair roofs using manufacturer-recognized brands including GAF, CertainTeed, and Owens Corning, which means warranty paperwork is straightforward and parts are genuinely available when we need them. For Sonoma’s high concentration of tile roofs, we regularly work with Boral clay tile as well. The practical advantage for you: when we need a matching tile, a specific underlayment, or a warranty-covered replacement piece, we’re not waiting a week for a distributor in another state. We’re pulling from supply channels that already serve Sonoma Valley contractors.
Common Roof Installation Problems We See in Sonoma Homes
- Wrong underlayment under a Class A surface: Sonoma sits in a Wildland-Urban Interface zone, and local inspectors require the entire roof assembly – not just the tile or shingles – to carry a Class A fire rating. We’ve seen jobs fail final inspection because a contractor installed Class A tile over standard felt.
- Concealed rot near the Plaza: On homes built between the 1880s and 1900s around the historic Plaza, tearing off an old wood shake roof routinely exposes rotted decking and undersized rafters that no one could see until the roof was open.
- Marine fog and moss pressure: Persistent fog through the Petaluma Gap keeps north-facing roof planes damp well into the afternoon. Moss and lichen spread under clay tile mortar, and where valleys and pipe penetrations aren’t re-flashed correctly, the dampness works into the underlayment.
- Wood shake under tile: Some Wine Country estates had tile installed directly over old wood shake decades ago. That layering hides the shake condition and violates current fire code the moment you pull a re-roofing permit in a WUI-designated area.
Pricing for Roof Installation in Sonoma, CA
Here’s what we quote in the real world of Sonoma’s roof market. A standard composition shingle roof on a 1,800 square foot ranch home runs roughly $14,500 – $21,000. A tile roof replacement on a 2,500 square foot Spanish Colonial Revival home near the Plaza typically lands between $26,000 and $45,000 depending on whether we’re reusing existing tile, the roof pitch, and what framing work the tear-off exposes. Ventilation upgrades add $800 – $3,500 as noted above. Decorative fascia or gutter replacement is priced separately. Every Mercer estimate is written, line-item, and delivered before any work starts. If we find hidden framing or waterproofing damage, we stop, show you photos, and put a change order in writing for your approval. Call (743) 200-8347 to schedule your free estimate.
We Also Serve Cities Near Sonoma
Our scheduling for Roof Installation in Sonoma also reaches the surrounding communities: Boyes Hot Springs, Petaluma, Novato, and Cotati. Dispatch is coordinated from the brand’s San Francisco Bay Area office, with local crews serving Sonoma directly. If you’re just outside the city line, call and we’ll confirm coverage for your street.
Serving Sonoma, CA - Our Local Coverage Area
We’re based in the Sonoma 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 Sonoma
Yes. In Sonoma’s WUI-designated areas, the entire roof assembly must be Class A fire-rated, including the underlayment beneath the shingles or tile. A Class A surface material over a non-rated underlayment will fail inspection, so we write the assembly spec into your quote from the start. Call (743) 200-8347 and we’ll confirm exactly what your property requires.
We typically find one or more of three things: cracked or undersized rafters, rotted decking where old wood shake trapped moisture, and waterproofing that was never done correctly around chimneys and valleys. We sister new framing to the existing structure, replace bad sheathing, and install a full ice and water shield membrane where code and common sense demand it. That framing work is quoted as a written change order before we proceed.
Sonoma Valley’s winter rain concentrates 25 – 30 inches between November and March, and the summer heat accelerates underlayment breakdown far faster than in the cooler coastal Bay Area. The marine fog that pushes through the Petaluma Gap adds constant dampness on north-facing planes. Under clay tile, that underlayment is doing all the real waterproofing work, so it has to be specified and installed to handle Sonoma conditions, not generic Northern California conditions.
We remove the growth and address the root cause: dampness and shade. That usually means cleaning debris, correcting valley flashing, and sometimes adding ventilation so the roof deck dries faster. Moss left in place will lift the tile and mortar and channel water where it doesn’t belong. The fix is part of a proper install, not an afterthought.
Line them up item by item and look hardest at three lines: the underlayment specification, the framing allowance, and the written warranty. In Sonoma, the underlayment line must say the assembly meets Class A WUI requirements. If one bid has a small framing allowance and the other has none, the one with none is assuming no surprises, which is rarely true on older Sonoma homes. Our written prices include a stated allowance for discovered framing or waterproofing work, and nothing proceeds beyond that allowance without your written approval. Call (743) 200-8347 for a free, written estimate you can compare properly.
Written by Grant Whitlock, Owner at Mercer Roofing, serving Sonoma and Sonoma Valley. Part of the Threshold Group family, founded in 2000.






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