Free roof inspection with deck photos before we talk money - GAF and Owens Corning certified installation
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AfterFast, Reliable Roof Repair Across Redwood City
Roof repair in Redwood City usually costs between $350 and $1,800 depending on what failed, and most smaller jobs take one day. We’re Mercer Roofing, and we’ve repaired thousands of roofs across the Peninsula, including plenty in Redwood City’s flatland tract neighborhoods and the steeper hillside streets of Emerald Hills and Farm Hill. If water is coming in or shingles are sliding, call us at (743) 200-8347. We’ll give you a written price before any work starts, and the technician who shows up will already be someone you’ve seen: we send their name and photo before they arrive.
Key Takeaways:
- Redwood City’s “Climate Best by Government Test” sun means shingles lose granules faster here than in foggy Peninsula towns.
- Salt air from the Bay corrodes standard fasteners and flashing years before their time.
- Every repair includes a written 365-Day Done Right Promise and a free second visit if our fix fails.
- A live person answers our phone 24/7, not a voicemail.
Why Mercer Roofing Is Redwood City’s Preferred Roof Repair Company
Homeowners in Redwood City call us because we treat the door as seriously as the roof. Before any technician steps onto your property, you get their name and photo. They arrive in a clean uniform, badged with photo ID, and they’ve already passed a background check through the Threshold Verified standard. That’s not a nice-to-have. For parents home alone with young kids or older homeowners who want to know exactly who’s coming, it’s the reason we get the call.
Our founder Grant Whitlock built Mercer Roofing in 2000 on a simple premise: write the price down, write the guarantee down, and show up as the person you said you’d be. That’s why we put the 365-Day Done Right Promise on every repair. If our fix fails within a year, we come back and make it right at no charge. The crews we dispatch to Redwood City know the local housing stock, from the 1940s tract homes west of El Camino Real to the complex hip-and-gable Craftsman bungalows near downtown. We know which roof slopes on your street take the worst UV, and we know what the winter atmospheric rivers do to a roof that’s already weakened by six months of Peninsula sun.
Metal Roof Repair in Redwood City
Metal roof repair in Redwood City handles a specific kind of failure: standing-seam and metal tile roofs that look fine from the ground but are losing the battle against salt air at the fasteners and seams. The first sentence of any honest conversation about metal roofs near the Bay is that the panel itself will outlast everything holding it down. What fails here are the screws, the neoprene washers, the seam sealants, and the flashing at penetrations. Coastal air corrodes standard steel screws inside of five to seven years. We replace them with stainless or hot-dip galvanized fasteners and reseal seams with marine-grade sealant rated for continuous UV and salt exposure.
Fastener and Seam Replacement
When a metal roof leaks in Redwood City, the water is almost never coming through the panel. It’s coming through a rusted screw, a cracked washer, or a seam that baked in the sun until the sealant turned brittle. We pull the failed fasteners, check the substrate for rot, install marine-grade replacements, and reseal the seam. A typical fastener replacement job runs $500 to $1,100 depending on how many fasteners have failed.
Flashing and Penetration Repair
Chimneys, vents, skylights, and pipe boots on metal roofs are the usual leak points. In Redwood City’s UV-then-downpour cycle, a small crack at a pipe boot becomes a water entry point during the first atmospheric river of November. We remove the old boot, inspect the surrounding decking, and install a new boot with a stainless clamp and a sealed base. Expect $400 to $900 for a single penetration repair on a metal roof.
Commercial Roof Repair in Redwood City
Commercial roof repair in Redwood City usually means flat or low-slope roofing on offices, retail storefronts, and multi-unit buildings stretching from the downtown corridor down El Camino Real to the industrial edges near Highway 101. These roofs fail differently than residential ones. We see ponding water after winter storms, split seams in single-ply membranes, and failed patches from previous repairs that never addressed the underlying decking. Our flat roof patch work starts with finding the actual water path, not just the visible stain on the ceiling. We cut back the failed membrane, inspect the insulation, replace what’s saturated, and seam in a new patch with the same material family as the existing roof.
Flat Roof Patch and Membrane Repair
A 10-by-10 membrane patch on a commercial flat roof in Redwood City runs $800 to $2,200 depending on membrane type and access. We work with TPO, EPDM, and modified bitumen. If the roof is older and the membrane is brittle from UV, we’ll tell you straight: patching may buy you two or three years, but a film of brittle membrane will continue to fail at the seams. We’ll give you the repair price and the replacement price side by side, in writing, before you decide.
Valley and Drainage Repair
Flat commercial roofs in Redwood City live and die by their drainage. When the scuppers and internal drains clog with leaf debris from the oaks around Atherton and the hills, water ponds, and seams separate. We clear the drainage path, repair the damaged seam, and often recommend adding a secondary overflow scupper if the building code and roof pitch allow. Ponding-related seam repairs usually land between $600 and $1,500.
Trusted Brands We Service in Redwood City
We install and repair roofs using manufacturer-recognized shingle brands including GAF, CertainTeed, and Owens Corning. For Redwood City homeowners, brand matters because not every shingle handles UV the same way. CertainTeed’s Landmark and GAF’s Timberline lines both offer granule adhesion that holds up under Peninsula sun better than budget three-tab products. For shake-to-composition conversions, which are one of the most common jobs we do in Redwood City, we often specify a Class A impact-rated shingle from GAF or CertainTeed to satisfy San Mateo County’s fire-hazard ordinance. We keep local stock of common matching shingle colors for Redwood City homes, so a repair on a 1990s CertainTeed roof doesn’t mean a three-week wait or an obvious patch.
Common Roof Repair Problems We See in Redwood City Homes
- UV granule loss on south- and west-facing slopes. Redwood City gets measurably more sun than Daly City or San Mateo. Architectural shingles that should last 25 years can start shedding granules at 15, leaving bare asphalt that leaks. We see it most on the flatland tract homes west of El Camino Real where roofs are shallow-pitched and the sun sits on the shingles all afternoon.
- Corroded fasteners from salt air. The Bay is close enough that marine air works on anything electro-galvanized. Shingle nails rust, let go, and shingles slide. We repaired a 1955 tract home in the Woodside Plaza neighborhood where the original wood shake had been replaced years ago with a Class A composition roof, but the builder used electro-galvanized nails that had rusted through, causing shingles to slide and expose the underlayment. Our crew pulled the affected shingles, replaced the corroded fasteners with hot-dip galvanized nails, installed a new ice and water shield along the eaves, and reset the drip edge to stop water from wicking into the fascia.
- Wood shake roofs that can’t be replaced in kind. San Mateo County’s fire-hazard ordinance prohibits replacing a failed wood shake roof with new shakes. If you own a 1940s – 1960s home in Redwood City with the original shake roof, the law says the next roof must be Class A. We walk homeowners through the shake-to-composition or shake-to-tile conversion every week.
- Atmospheric river leaks at valleys and chimneys. The November-to-March downpours hit roofs that spent six months baking. The combination stresses valley metal and chimney flashing until they fail. These are the leaks that show up as a drip in the living room during the second storm of the season, not the first.
Pricing for Roof Repair in Redwood City, CA
Here’s what Redwood City homeowners can expect to pay. A shingle replacement on a small section runs $350 to $700. Leak repair, where we find the source, repair the flashing or shingle, and seal the area, runs $400 to $900. Flashing repair at a chimney or valley runs $500 to $1,200. Vent boot replacement runs $250 to $450. Valley repair runs $600 to $1,400. Flat roof patches run $500 to $1,400 on residential roofs and $800 to $2,200 on commercial. These are written, fixed prices, not estimates that change once we’re on the roof. Call (743) 200-8347 and we’ll give you a line-item price before any work starts.
We Also Serve Cities Near Redwood City
Our Roof Repair team works throughout the mid-Peninsula. Beyond Redwood City, we repair roofs in Atherton, Menlo Park, San Carlos, and Palo Alto. The housing stock changes from street to street, and so does the right repair. Call us and we’ll tell you exactly what your roof needs.
Serving Redwood City, CA - Our Local Coverage Area
We’re based in the Redwood City 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 Repair in Redwood City
Redwood City repairs often cost slightly more because of the material upgrades the climate requires. We use hot-dip galvanized or stainless fasteners, marine-grade sealants, and UV-rated materials that hold up to the city’s intense sun and salt air. We don’t put electro-galvanized nails in a Redwood City roof because they’ll rust out in five to seven years and you’ll be paying for the repair twice. The $50 to $150 difference on a typical repair is the cost of fasteners and sealants that won’t fail early. Call (743) 200-8347 for an exact quote on your roof.
No. San Mateo County’s fire-hazard ordinance no longer allows wood shake roofs to be replaced with new wood shakes. The replacement roof must be Class A fire-rated, which means composition shingles, concrete tile, or another non-combustible material. This applies to any re-roofing permit pulled in Redwood City. We do shake-to-Class-A conversions regularly and will walk you through the options, the cost, and the permit process. Call (743) 200-8347 to schedule a free estimate.
That slogan is a real claim about sun exposure, and it means your shingles are aging faster than you think. Redwood City gets more annual sunshine than nearly any other city on the Peninsula, which accelerates UV degradation on asphalt shingles and EPDM membranes. Then winter atmospheric rivers dump intense rain on a roof that’s already UV-weakened. The combination is why we see leaks at valleys and chimneys here that wouldn’t show up for another decade in Daly City. If your roof is over 15 years old, call us at (743) 200-8347 and we’ll do a free visual assessment.
We use hot-dip galvanized nails as standard on virtually every shingle repair in Redwood City. When the job involves a metal roof, we use stainless steel screws with neoprene washers. Standard electro-galvanized nails corrode quickly in the Bay’s marine air and fail within a few years. On repairs near the coast or on steep slopes in Emerald Hills, we may step up to copper or stainless fasteners depending on the material. The fastener upgrade is included in every quote we write, not an add-on. Call (743) 200-8347 and we’ll tell you exactly what your roof needs.
Yes. We repair standing-seam metal roofs, metal tile roofs, and metal roofing on commercial buildings throughout Redwood City. The key is using materials that can handle the salt air: stainless fasteners, marine-grade sealants, and replacement flashing cut from the same gauge metal as the existing roof. A standard metal roof repair in Redwood City runs $500 to $1,100 for fastener and seam work, and $400 to $900 for flashing and penetration repairs. We’ll also tell you if the roof’s fastener pattern is the problem and whether a broader fastener replacement makes more sense than patching one spot. Call (743) 200-8347 and describe what you’re seeing, and we’ll give you a written price.
Call Mercer Roofing for Roof Repair in Redwood City
If your roof is leaking, shedding granules, or showing rust at the fasteners, call us at (743) 200-8347. You’ll speak to a live person, not a voicemail. We’ll schedule a free estimate, send you the technician’s name and photo before they arrive, and hand you a written price before any work starts. Every repair includes our 365-Day Done Right Promise: if it’s not right within a year, we make it right. That’s how Grant Whitlock has run Mercer Roofing since 2000, and it’s how we serve Redwood City today.
Written by Grant Whitlock, Owner at Mercer Roofing, serving Redwood City since 2000.