Free roof inspection with deck photos before we talk money - GAF and Owens Corning certified installation
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AfterOwens Corning Roofing in San Francisco, CA | Brennan Roofing
We provide independent Owens Corning roofing service in San Francisco, from flat-roof patch work in the Sunset to full Duration shingle replacements in the Richmond. The thing that makes our Owens Corning work here different is that we know the product line and we know the city’s parapet-heavy, fog-soaked row houses. If your Owens Corning roof is leaking, call (361) 320-9467 for a free estimate with the price in writing before any work starts.
Why San Francisco Residents Choose Us for Owens Corning Service
We’ve torn off and replaced thousands of squares of Owens Corning shingles and membrane across San Francisco’s pre-1950 row houses, from Sunset tar-and-gravel to Pacific Heights flat decks. As an independent contractor, we know Owens Corning’s product line inside and out, but we’ll tell you straight when a roof repair in San Francisco makes more sense than a full replacement. Travis Oakley, our owner, still pulls his own inspections and will tell you flat-out if a patch job will hold or if you’re throwing money at a roof that’s already done. That’s the Garrison Standard: a written price before any work starts, background-checked uniformed technicians on your roof, and a full-year written guarantee on every job.
We’re not a manufacturer-authorized dealer. We’re an independent Owens Corning service provider, which means we answer to you, not to a corporate program. We also know the difference between a roof that needs a $900 flashing repair and one that needs a $22,000 tear-off, and we’ll tell you which one you’re actually looking at. Learn more about our Owens Corning sales & service.
Common Owens Corning Roofing Problems We Solve in San Francisco
- Cracked parapet flashings on flat roofs. Water tracks behind the membrane and shows up inside walls. San Francisco’s parade of wet winters and foggy summers means these cracks open up every few years, and when they do, water follows the parapet right into the wall cavity. We replace the flashing with Owens Corning WeatherLock and re-seal the membrane edge.
- Ponding water on low-slope roofs. Repeated winter storms leave standing water on flat and low-slope Owens Corning roofs, which accelerates granule loss on shingles and breaks down modified-bitumen membranes. We check your drains and scuppers when we do any Owens Corning work because a clogged drain is often the real reason the shingles are failing.
- Clogged roof drains and scuppers. San Francisco’s wood-frame Victorian and Edwardian homes rot fast when water backs up under shingles. We see this all the time in the Mission and Noe Valley, where old downspouts feed into shared drains that no one has cleaned in a decade.
- Mildew and delamination from poor attic ventilation. Pre-1950 homes in San Francisco rarely have proper roof ventilation, and the city’s constant moisture means Owens Corning underlayments can delaminate from the decking. Before we lay new shingles, we check the airflow and fix it if it’s wrong. Otherwise we’re putting new material over the same failure.
- Leaks around skylights and light wells. Interior light wells are common in San Francisco row houses, and the flashing where the roof meets the light well is a chronic leak point. Owens Corning shingles can’t do their job if the flashing detail is compromised, so we rebuild that transition properly.
Owens Corning Service in San Francisco: What Local Conditions Mean for Your Equipment
San Francisco’s party-wall construction changes how Owens Corning roof work gets done. Most of the city’s flat and low-slope roofs sit between shared walls, so flashing tie-ins cross onto your neighbor’s side. In dense neighborhoods like the Sunset, that means we often need to coordinate access with the house next door before we can properly seal an Owens Corning membrane against the parapet. That step can add days or even a couple of weeks to a project, and it’s something a roofer from outside the city won’t expect until they’re standing on the roof. We plan for it from the first estimate. We also know that after the first big November storm, flat tar roofs across the Sunset, Richmond, and Mission fail all at once at cracked parapet flashings and clogged drains. When you call us in that first dry week, we already know what we’re going to find.
Owens Corning Models & Products We Service in San Francisco
We install and repair the Owens Corning lines that actually show up on San Francisco roofs: Duration for steep-slope shingle work on pitched Edwardian gables, Oakridge for homeowners who want a step down in price without losing the architectural look, Supreme for three-tab repairs and accessory structures, and WeatherLock for the underlayment and flashing barrier work that matters most on flat and low-slope roofs. When parts are available, we use Owens Corning OEM shingles, underlayments, and flashing components. For older San Francisco homes where matching is impossible, we source high-quality aftermarket parts that meet or exceed the original spec. We stock common WeatherLock flashing materials locally so flat-roof patch work in San Francisco doesn’t wait on a freight shipment.
Owens Corning Service Pricing in San Francisco
Flat roof patches on Owens Corning membranes in San Francisco typically run $450 to $1,200 depending on how much flashing and membrane gets replaced. A parapet flashing repair with new WeatherLock usually lands between $900 and $2,400. Full Owens Corning roof replacements on a standard San Francisco row house run $14,000 to $28,000, with the spread driven by tear-off layers, decking condition, and whether we need neighbor access for party-wall tie-ins. Every estimate is written, itemized, and locked before any work starts. No change orders at the door. Call (361) 320-9467 to schedule a free estimate and we’ll put the number on paper.
Serving San Francisco, CA - Our Local Coverage Area
We’re based in the San Francisco 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 – Owens Corning Roofing in San Francisco
Yes, and this is one of the most common repairs we do in San Francisco. The fix usually means removing the damaged shingles at the parapet, replacing the flashing with Owens Corning WeatherLock, and re-sealing the membrane edge. If the leak has been running for a while, we’ll check the decking underneath for rot before closing anything up. Call (361) 320-9467 and we’ll give you a written estimate.
Most full Owens Corning replacements on San Francisco row houses take 3 to 7 working days once we’re on site. Party-wall coordination with a neighbor can add time before we start, and rainy days in the November through March window push work out. We don’t tear off in the rain, so we schedule around the forecast. Call (361) 320-9467 for a timeline on your specific roof.
No. Duration shingles are built for pitched roofs, and most San Francisco flat roofs have too little slope for them to shed water properly. On flat or very low-slope roofs, we recommend Owens Corning membrane systems or modified bitumen instead. Laying Duration on a flat roof is a shortcut, and we won’t do it. Call (361) 320-9467 and we’ll tell you what your roof actually needs.
Constant moisture is the main culprit. San Francisco’s fog keeps roofs damp year-round, and when the attic space doesn’t ventilate properly, that moisture gets trapped under the shingles. Over time, the underlayment delaminates and granule loss accelerates. Poor parapet flashing details make it worse because water gets behind the membrane instead of running off. We inspect the ventilation and flashing on every Owens Corning service call in San Francisco because those two factors explain most early failures.
Usually. If your Owens Corning shingles are a current production color in Duration or Oakridge, we can source the OEM match. For discontinued colors or older lines, we’ll find a close aftermarket match and show it to you before we install it. If more than 30% of the roof is damaged, replacement is usually the smarter long-term move, and we’ll tell you that straight. Call (361) 320-9467 for an honest assessment.
Service Areas Near San Francisco
We serve the full San Francisco service area, including the Sunset, Richmond, Mission, Noe Valley, and Pacific Heights neighborhoods. For Owens Corning work in the Central Valley, see our Owens Corning service in Fresno and Owens Corning service in Sacramento pages.
Book Your Owens Corning Service in San Francisco Today
If your Owens Corning roof is leaking, don’t wait for the next storm to find out how bad it is. Call (361) 320-9467 today and we’ll schedule a free estimate with the price in writing before any work starts. A roof that’s squared away doesn’t need a sales pitch.
Written by Travis Oakley, Owner at Brennan Roofing, serving San Francisco since 2000.