Owens Corning
Architectural shingles
Metal roofing
Tile roofingFree roof inspection with deck photos before we talk money - GAF and Owens Corning certified installation
Why San Diego Homeowners Choose Owens Corning Roofing
Mercer Roofing Co San Diego provides independent Owens Corning roofing repair and installation across San Diego, offering San Diego Owens Corning service that specializes in Duration, TruDefinition Duration STORM, Oakridge, and Supreme shingle lines. Our crews know how these shingles actually behave in coastal fog, salt air, and Santa Ana wind conditions, which means we diagnose problems other roofers misread. We are an independent Owens Corning service provider, not a manufacturer-authorized dealer, so our recommendations are based on what holds up on San Diego roofs, not what a corporate sales program tells us to push. Call (619) 810-5520 for a free estimate.
Grant Whitlock, owner of Mercer Roofing Co San Diego, has spent nearly two decades watching how Owens Corning products age on San Diego homes. He walked every Owens Corning job personally before founding this location, and that habit hasn’t changed. The San Diego climate does specific things to asphalt shingles: marine-layer moisture works into the asphalt matrix while afternoon UV bakes the granules. Pick the wrong shingle line for the wrong slope, and you’ll be back on that roof in eight years wondering what happened. Pick the right one, install it with proper ventilation, and a 30-year shingle actually approaches 30 years here.
Why Trust Mercer Roofing Co San Diego for Your Owens Corning Roofing?
Our technicians spend more time on Owens Corning roofs than on any other brand in San Diego. That familiarity matters when a TruDefinition Duration STORM shingle lifts at the sealant strip after a Santa Ana event, or when Oakridge shingles start cupping along the eaves where fog sits longest. We know which failure is cosmetic, which one is structural, and which one means the underlayment underneath has already started to fail. The OEM-versus-aftermarket question comes up on nearly every repair call. We stock Owens Corning OEM shingles and matching hip and ridge caps locally in San Diego for fast turnaround on roof repair jobs. For older roofs with heavy granule loss, we’ll tell you honestly when patching won’t blend and a targeted replacement or full reroof makes more sense.
Grant grew up in Los Angeles and learned the trade through Los Angeles Trade-Technical College’s building construction program before spending the better part of two decades on San Diego roofs. His crew has replaced more than a few storm-damaged roofs in Clairemont Mesa, and he still walks every job himself before a single nail goes in. A roof shouldn’t be something you worry about, that’s what we’re here for. When you call Mercer Roofing Co San Diego, the technician who shows up is background-checked, identity-verified, and arrives in a clean uniform with a photo ID badge. We send their name and photo before they arrive, so you know exactly who is walking up your driveway.
Styles & brands we work with
Common Owens Corning Roofing Problems We Fix in San Diego
- Granule loss on Duration shingles from UV exposure. San Diego’s inland valleys get intense afternoon sun, and after a decade of thermal cycling, the granule adhesion on Duration shingles breaks down. You’ll see bald spots where the asphalt matrix is exposed. That exposed asphalt now absorbs more heat, accelerating aging across the whole slope. We see this most often on west and south-facing roof planes in areas like Clairemont and Allied Gardens.
- Wind uplift at the sealant strip on TruDefinition Duration STORM shingles. These shingles are engineered for high-wind markets, but the sealant strip still relies on proper installation temperatures and clean contact. During Santa Ana wind events, we see lift at eaves and rakes where the original installer didn’t get a clean seal. A lifted shingle isn’t just cosmetic, it lets wind-driven rain reach the underlayment.
- Curling and cupping at the edges of Oakridge shingles from marine-layer moisture. Coastal fog lingers on north-facing slopes in San Diego for hours each morning. Oakridge shingles absorb that moisture, and when the sun hits them, the edges curl. This is progressive; once the edges lift, they catch wind more easily and the problem compounds. We fix this with targeted shingle replacement when caught early, or full slope replacement when it’s widespread.
- Blistering on Supreme shingles from trapped moisture in the asphalt matrix. Supreme is Owens Corning’s entry-level line, and it’s more sensitive to installation conditions. If the shingles were installed over a damp deck or the asphalt mix had moisture during manufacturing, small blisters form on the flat surfaces. When the blisters pop, they become miniature granule-loss points. We commonly find this on 1960s and 1970s San Diego ranch homes that still carry their original Supreme or comparable shingles.
- Deteriorated underlayment at skylight curbs and valleys. The shingle often isn’t the problem; the underlayment beneath it is. On Owens Corning roofs in San Diego, we regularly find failed underlayment at skylight curbs, valleys, and sidewalls. The shingles look fine, but water staining inside tells a different story. A proper fix requires removing the surrounding shingles, replacing the underlayment, and re-flashing the penetration.
Owens Corning Parts & Our Repair-vs-Replace Approach
We use Owens Corning OEM shingles and matching hip and ridge caps for repairs whenever possible. On newer roofs with minimal fading, OEM materials blend seamlessly into the existing field. On older Oakridge or Supreme roofs with significant granule loss, aftermarket patching rarely matches, and it can shorten the roof’s remaining life by creating uneven wear patterns. We’ll tell you when a patch is the right call and when it isn’t.
We stock Owens Corning Duration and Oakridge shingles locally in San Diego, along with Owens Corning hip and ridge accessories, for faster turnaround on repair calls. A recent job in Clairemont involved a 12-year-old TruDefinition Duration STORM roof with water staining around a skylight. The original installer had used a generic adhesive underlayment at the skylight curb, and it had deteriorated enough to let wind-driven rain wick under the shingles. We removed the surrounding shingles, replaced the underlayment with high-temperature ice-and-water shield, re-flashed the curb, and reinstalled the existing Duration STORM shingles with fresh sealant. The homeowner kept their roof; the leak is gone. Call (619) 810-5520 if you’re seeing staining and want an honest assessment.
Our general rule: if granule loss covers less than 15 percent of a slope and the shingles still lie flat, targeted replacement makes sense. Beyond that, we’re talking about a reroof. Every repair we make carries a written guarantee, and if it fails within 365 days, we make it right at no cost.
Our Owens Corning Service Process – Step by Step
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Diagnosis. We inspect the roof plane by plane, checking granule adhesion, sealant strip integrity, underlayment condition at penetrations, and attic ventilation. Owens Corning shingles fail differently depending on the line, the slope, and the exposure, so we don’t guess.
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Written estimate. You get a written price before any work starts. No conditional pricing, no change orders unless you ask for additional work.
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Repair or install. We use Owens Corning OEM materials where blending matters, proper underlayment replacements where the leak actually starts, and manufacturer-recommended fastening patterns.
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Testing. After the repair or install, we water-test critical areas and verify the sealant strip has set correctly on windy exposures. If it hasn’t, we fix it before we leave.
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Warranty. Every Owens Corning repair includes our written guarantee, covered for 365 days, with a free second visit if the repair fails.
See the difference
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AfterOwens Corning Products We Service & Install in San Diego
We service and install the full Owens Corning residential shingle lineup common in San Diego: Duration architectural shingles, TruDefinition Duration STORM high-wind architectural shingles, Oakridge architectural shingles, and Supreme 3-tab shingles. We also install Owens Corning hip and ridge caps, starter strips, and recommended underlayments. Our sub-service focus areas include architectural shingle installation, flashing repair, and valley repair, three areas where San Diego’s coastal conditions and Santa Ana winds create the most callbacks. We also provide El Cajon Owens Corning service for homeowners in that area.
We Also Service These Brands
While Owens Corning occupies a large share of our San Diego work, we also service and install GAF and CertainTeed roofing systems. If your home carries a different manufacturer’s warranty, we honor it and use OEM-compatible materials. The right shingle for your roof depends on your slope, your exposure, and your microclimate, not on what one manufacturer markets.
FAQs – Owens Corning Roofing Service in San Diego
Yes, Duration shingles hold up well in coastal fog areas when properly installed with adequate ventilation. The marine layer in San Diego’s coastal neighborhoods keeps north-facing slopes damp for hours each morning, and Duration’s tighter granule adhesion and heavier mat help resist the moisture absorption that causes cupping on lighter shingle lines. The real variable is ventilation; a well-ventilated attic pulls moisture out of the deck before it saturates the shingles. Call (619) 810-5520 if you’re seeing edge curl on a north-facing slope and want to know whether it’s a warranty issue or an installation issue.
Usually, yes, if the roof is under about ten years old and the existing shingles haven’t faded significantly. We stock Owens Corning Oakridge in common San Diego colors and can pull matching hip and ridge caps locally. On older Oakridge roofs with visible fading or granule loss, a patch will stand out no matter how well we match the color, and a targeted slope replacement is often the better call. We’ll show you the options and let you decide.
Granule loss on Owens Corning shingles in San Diego is usually caused by prolonged UV exposure breaking down the asphalt’s grip on the ceramic granules, combined with thermal cycling from hot afternoons and cool nights. Some granule loss is normal, especially in the first year after installation. It becomes a failure signal when you see bald asphalt patches larger than a quarter, or when granules are collecting in your gutters every season. That means the asphalt matrix is exposed and breaking down. We can tell you whether what you’re seeing is normal or terminal. Call (619) 810-5520 for an inspection.
No, Owens Corning’s TruDefinition Duration STORM shingles are actually engineered for high-wind markets and carry a higher wind rating than many competitors. The vulnerability in San Diego isn’t the shingle itself; it’s the sealant strip’s initial adhesion. If the shingles were installed on a cool morning or over a dusty deck, the sealant never fully bonded, and Santa Ana gusts find those weak points at eaves and rakes. We see this on Owens Corning roofs installed by crews who rushed the job, not as a defect in the product.
Yes, in many cases a metal roof can be installed over an existing Owens Corning shingle roof, but San Diego’s coastal climate makes this a decision to approach carefully. The existing shingles must be structurally sound, the deck must be dry, and the marine-layer moisture trapped between metal and shingle needs to be addressed with proper underlayment. If your Owens Corning roof already has granule loss or moisture damage, a tear-off is the better investment. We’ll assess and give you a straight answer either way.
Owens Corning roofing in San Diego typically runs $6.50 to $9.50 per square foot installed for Duration architectural shingles, depending on tear-off, decking condition, roof pitch, and accessibility. A typical 1,800-square-foot single-story ranch in San Diego might land between $12,000 and $17,000 for a full Duration reroof. TruDefinition Duration STORM runs slightly higher due to the heavier mat. Repairs are priced by scope, not by square foot; a skylight curb re-flash with new underlayment typically falls in the $800 to $1,400 range. Call (619) 810-5520 for an exact quote, estimates are free and written.
Book Your Owens Corning Service in San Diego, CA
If your Owens Corning roof is showing granule loss, lifted shingles, or water staining around penetrations, and you need Owens Corning repair in National City or surrounding areas, call Mercer Roofing Co San Diego at (619) 810-5520. We’ll send a background-checked, photo-badged technician whose name and photo you’ll have before they arrive. You’ll get a written price before any work starts, and every repair carries our 365-Day Done Right Promise in writing.
Written by Grant Whitlock, Owner at Mercer Roofing Co San Diego, serving San Diego since 2000.