Free roof inspection with deck photos before we talk money - GAF and Owens Corning certified installation
Before
After
Before
After
Before
AfterFast, Reliable Roof Installation Across San Anselmo
Roof installation in San Anselmo means something specific: older wood-frame homes, tight hillside lots, and CAL FIRE code requirements that change what materials you can use. A full tear-off and re-roof on a typical 1,200 – 1,800 sq ft San Anselmo home runs $14,000 – $28,000, depending on decking condition, pitch, and the fire-rated material you choose. We’ve worked the Scenic Avenue hillsides, the flats near Creek Park, and the streets around Wade Thomas Elementary, so we know what these roofs look like under the shingles before we ever pull the first one off. If you need a straight answer on cost or scope, call (743) 200-8347 and we’ll walk you through it.
Why Mercer Roofing Is San Anselmo’s Preferred Roof Installation Company
Most roofing calls in San Anselmo start the same way: a homeowner opens the door to someone they’ve never met and hopes for the best. We do it differently. Before our crew arrives, you get the technician’s name and photo sent to you. When they knock, they’re in a clean, marked uniform and they hand you a photo ID badge. That’s the Threshold Verified standard, and every independently owned Threshold Group location is contractually held to it.
Grant Whitlock leads our team, and he’s built our San Anselmo work around one principle: write it down before you build it. Every project gets a written price before work starts. Every repair includes a written guarantee, backed by our 365-Day Done Right Promise. If it’s not right within a year, we make it right. That’s not a slogan. It’s on paper.
We also answer the phone. Twenty-four hours, seven days, a real person picks up. No voicemail, no call-back form. When you’re worried about a roof on a rainy February night in San Anselmo, you want to hear a voice.
Roof Flashing Installation in San Anselmo
Roof Flashing Installation in San Anselmo deals with the metal pieces that direct water away from the places roofs always leak: chimneys, side walls, valleys, dormers, and vent pipes. In a town where redwood needles and oak leaves pile up in roof valleys all year, flashing does more than seal a seam. It keeps decomposing organic matter from turning a minor gap into a steady drip into the decking below.
Flashing work on a San Anselmo re-roof typically runs $800 – $2,400 depending on how many penetrations your roof has and whether we’re replacing galvanized with copper or a higher-grade coated steel. On older homes, we often find existing flashing nailed through improperly or corroded at the fold lines, especially where a 1920s chimney meets a re-shingled roof plane.
Valley and Chimney Flashing Work
Valleys collect more water than any other part of a roof, and San Anselmo’s tree canopy drops constant debris into them. We inspect valley flashing for rust-through and missing step flashing at chimneys before laying new underlayment. If we find rot at the valley edges, we cut it out and replace that decking before sealing anything.
Party-Wall Flashing on Shared Roof Lines
Homes that share a wall or a roofline need flashing detail that a detached spec house never thinks about. We run continuous step flashing up the shared wall and tie it into a reglet cut above the roofline so water can’t track sideways into the neighbor’s ceiling cavity. Skipping that coordination delays inspections and sours the block fast.
TPO Roofing Installation in San Anselmo
TPO Roofing Installation in San Anselmo is the flat-roof solution we recommend for additions, detached studios, and most low-slope or flat sections you see on hillside remodels. TPO is a single-ply thermoplastic membrane, heat-welded at the seams, and it reflects heat better than older torch-down systems. On a hillside lot where a flat roof over a carport or a dormer takes direct afternoon sun, that reflectivity keeps the structure below noticeably cooler.
A TPO installation on a San Anselmo flat roof section runs $9,000 – $16,000 for a typical 400 – 800 sq ft area, including tear-off of the old membrane, insulation board replacement where saturated, and new perimeter metal. Staging on a hillside lot with no flat ground adds labor hours, which is part of why flatland bids for the same square footage rarely match what San Anselmo actually costs.
Hillside Staging and Access for Flat Roofs
When there’s no side yard, we stage membrane rolls and insulation boards in the driveway or on a street-legal dump trailer and shuttle materials up in lifts. That access cost is real and we price it line-item, not buried in a vague “labor” line. You’ll see it.
Drainage Tie-Ins for TPO Sections
A TPO membrane only performs as well as the drains and scuppers feeding it. On San Anselmo homes where older flat sections drain into gutters that then dump toward the creek corridor, we check for undersized downspouts and debris traps before welding a single seam. If drainage is wrong, the new roof inherits the old roof’s water problem.
Trusted Brands We Service in San Anselmo
We install and repair roofs using manufacturer-recognized brands including GAF, CertainTeed, and Owens Corning, and we’re authorized to work with Atlas, Tamko, and Boral systems. For San Anselmo’s CAL FIRE shake-to-Class-A conversions, we stock composite shake-profile shingles in the local distribution centers so homeowners don’t wait weeks for a period-appropriate material. Product lead times matter on hillside tear-offs, and we can usually get materials staged within days of the signed quote.
Common Roof Installation Problems We See in San Anselmo Homes
- Rotted original decking on 1910 – 1950 wood-frame homes. Much of San Anselmo’s pre-war housing stock sits on original 1x decking that’s thinner than modern OSB and often rotted at valleys, eaves, and penetrations. We replace it before new underlayment goes down. Out-of-town bidders routinely miss this until the tear-off exposes it, then hit you with a change order.
- Wood shake that violates current CAL FIRE material rules. Homes in the High Fire Hazard Severity Zones above the valley floor are code-required to convert to Class A fire-rated assemblies at re-roof. That means the shake comes off and a Class A composite, steel shake-profile, or other rated assembly goes on.
- Blocked drains feeding San Anselmo Creek’s flood-prone corridor. A roof that holds water at the downspouts isn’t a roof problem, it’s a drainage problem. We inspect the gutter and downspout geometry as part of every installation quote because in this valley, a blocked downspout at the wrong spot puts water against a foundation that’s already in a flood-mapped area.
- Party-wall coordination failures. On narrow lots with shared walls, a roof line often crosses a property boundary. Neighbor notice, flashing detail, and working during permitted hours aren’t optional courtesies here. They’re what keeps the job moving and the block from turning hostile.
On a narrow hillside lot off Scenic Avenue, our crew replaced a failing wood shake roof on a 1920s Craftsman where the original 1x decking had dry-rotted around the valleys and the rafter spacing couldn’t carry a heavy tile system. We staged materials in the driveway and on a street-legal dump trailer because there was no side yard, replaced roughly eight squares of decking, laid ice and water shield through the valleys and along the shared party wall, and set a Class A composite shake-profile shingle that satisfied both the fire code and the owner’s period-look expectation. Neighbors were notified two days ahead, and we ran compressors inside the town’s permitted work hours to keep the shared-wall household onside.
Pricing for Roof Installation in San Anselmo, CA
A full tear-off and re-roof on a typical San Anselmo home runs $14,000 – $28,000 for architectural composition shingles, with composite shake-profile Class A systems landing in the $22,000 – $38,000 range depending on square count and decking condition. Flashing work adds $800 – $2,400, and TPO sections on flat additions run $9,000 – $16,000 for typical 400 – 800 sq ft areas. Decking replacement, which older San Anselmo homes need more often than newer ones, adds $2.50 – $4.50 per sq ft. What moves the number most on a tight hillside lot is access: staging room, roof pitch, and whether we can get a dump trailer close. Call (743) 200-8347 and we’ll give you a written line-item quote after a roof inspection. The estimate is free, and the price you see is the price you sign.
San Anselmo’s hillside streets above the valley floor fall within CAL FIRE High Fire Hazard Severity Zones, so nearly every pre-WWII Craftsman and Colonial Revival home here must convert its original wood shake to a Class A fire-rated assembly at re-roof. That’s a code-driven material swap that flatland neighbors like San Rafael rarely face at the same density. It changes the product we recommend, the underlayment we lay, and the way we bid the job. A generic Roof Installation page can’t tell you that. We deal with it every week.
We Also Serve Cities Near San Anselmo
Our Roof Installation in San Anselmo service area extends to the towns around the valley floor and over the ridge. We work in Fairfax, Kentfield, San Rafael, and Larkspur, covering the same hillside access and fire-code territory that defines Marin roofing work. If you’re a few minutes down the road, the same crew and written-pricing process apply.
Serving San Anselmo, CA - Our Local Coverage Area
We’re based in the San Anselmo 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 San Anselmo
If your home sits in a CAL FIRE High Fire Hazard Severity Zone, state and local code requires any new roof assembly to meet Class A fire rating standards. That means original wood shake must be replaced with a Class A material like composite shake-profile, steel shake-profile, or architectural composition rated for the fire zone. We’ll confirm your specific designation when we inspect the roof and show you the code reference, not just tell you it’s required.
A hillside lot with no side yard changes where we can stage materials, how close a dump trailer can get, and how many trips the crew takes to move debris. We line-item that access cost rather than folding it into a rounded labor figure. If your driveway won’t fit a trailer, expect a slightly higher line for material handling and a realistic conversation about work hours, especially if shared walls are involved. Call (743) 200-8347 and we’ll tell you what applies to your specific street.
On many San Anselmo homes built between 1910 and 1950, yes. The original 1x decking is often too thin, too widely spaced, or too rotted at the valleys and eaves to hold new underlayment and fasteners properly. We assess decking condition during the inspection and include replacement in the written quote so it doesn’t become a surprise change order on tear-off day.
We notify adjacent households at least two days before we start, explain the scope and the work-hour plan, and coordinate flashing detail at the shared wall so water can’t migrate into their ceiling. We run compressors inside the town’s permitted work hours. It’s simple courtesy, and it prevents the kind of inspection delay that happens when a neighbor wasn’t told and makes a noise complaint on day one. Call (743) 200-8347 for an exact quote on a shared-roofline job.
Yes, and we build for it. San Anselmo’s tree canopy dumps redwood needles and oak leaves into valleys and gutters year-round, which means granule loss and moss growth happen faster here than in drier inland Marin. We recommend leaf guards on gutters and we inspect valley flashing and downspout sizing as part of every installation. A roof that ignores the debris load just accelerates its own wear.
Call Mercer Roofing for Your San Anselmo Roof Installation
You’ll know who’s coming to your door before they arrive, and you’ll know what the job costs before we start. Written price, written guarantee, and a live person on the phone at (743) 200-8347, 24/7. We serve all of San Anselmo, from the hillside streets above the valley to the flats near Creek Park. If your roof needs replacing and you want the scope handled correctly the first time, call us today to schedule your free estimate.
Written by Grant Whitlock, Owner at Mercer Roofing, serving San Anselmo since the company’s founding in 2000.