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Owens Corning Roofing in Simi Valley, CA | Mercer Roofing Co Woodland Hills
We provide independent Owens Corning roofing service across Simi Valley, and the thing that separates our work here is simple: we’ve torn off enough aging roofs in this city to know exactly how Owens Corning products hold up when Santa Ana winds hit a 1960s tract home. You get real diagnosis, real pricing, and a written guarantee before any work starts. Call (341) 217-2677 for a free estimate.
As an independent Owens Corning service provider, our crews have installed and repaired every major Owens Corning line across Simi Valley’s ranch-style tracts and hillside custom builds. We work with Owens Corning sales & service distribution partners to source factory-match shingles and underlayments, though we are not affiliated with or authorized by Owens Corning. That independence means we recommend what actually works for your roof, not what a corporate program tells us to push. Grant Whitlock, our owner, learned the trade through the construction technology program at Los Angeles Trade-Technical College, and he’s the kind of person who will tell you when a repair is enough and when it isn’t, and put that in writing before anyone picks up a nail gun.
Why Simi Valley Residents Choose Us for Owens Corning Service
Most roofing companies in Simi Valley can install shingles. Fewer can tell you why a specific Owens Corning product failed on your specific street. We keep an Owens Corning product library and factory training materials in our shop for our technicians, and we report recurring field failures back through our distribution rep so local inventory decisions reflect what actually happens on Simi Valley roofs. That’s not marketing language, it’s how we work.
Every technician who arrives at your door is background-checked, identity-verified, and in a marked uniform with a photo ID badge. You get their name and photo before they show up. For homeowners who want to know exactly who is walking up their driveway, that matters. And every repair we complete includes a written guarantee, free second visit if it fails, and a written price before any work begins.
Styles & brands we work with
Common Owens Corning Roofing Problems We Solve in Simi Valley
- Premature granule loss on Duration shingles. Simi Valley’s intense UV exposure, especially on south-facing slopes, accelerates surface erosion. We see Duration roofs here that look ten years older than their actual age. We can assess granule loss, identify whether the shingle still has structural life, and replace affected slopes when needed.
- Lifting and cracking along gable edges. Santa Ana winds in fall put real stress on Oakridge and Supreme shingles, particularly where nails were overdriven or missed the nail strip during original installation. We repair wind-lifted shingles and reinforce gable edges with proper nailing patterns.
- Deck Defense underlayment breakdown at side laps. When Owens Corning synthetic underlayment is left exposed to prolonged direct sunlight before shingle installation, the side laps can fail. We see this on re-roofs that stalled partway through Simi Valley’s long dry summers. The fix is proper sequencing and, where needed, replacing compromised underlayment sections.
- Starter strip nail corrosion on Hip & Ridge caps. Trapped moisture behind ridge vents corrodes the nails, especially on older Simi Valley homes with original 1x sheathing gaps. We catch this during inspections and replace the affected starter strip and ridge caps.
- Leaking valleys on 1960s and 1970s ranch homes. The older tracts in Simi Valley, like the Bird Streets off Erringer Road, often have valley flashing that was never adequate or has corroded over decades. Our valley repair work includes new flashing, fresh underlayment, and matching Owens Corning shingles cut to the valley line.
Owens Corning Service in Simi Valley: What Local Conditions Mean for Your Equipment
Here’s something specific about Simi Valley that shapes how Owens Corning roofing work plays out here, and it would not be equally true in Woodland Hills or Agoura Hills: the Bird Streets tract off Erringer Road still has original spaced sheathing under wood shake from the 1960s. On a 1972 ranch on Avenida Simi, our crew removed leaking wood shake and found original 1×6 spaced sheathing that could not support Owens Corning Deck Defense. We resheathed the entire 18-square roof with 7/16 OSB, then installed Owens Corning Duration in Driftwood with matching Hip & Ridge, replacing two failed valleys that had been leaking into the den. The homeowner had been told by another contractor they could just overlay, but our tech’s inspection caught the sheathing issue and prevented a future blow-off. That’s the difference between a company that looks at your roof and one that actually knows what’s under it.
This resheathing requirement is not optional. Owens Corning installation instructions and current building code require a solid deck before Deck Defense and Duration shingles go down. In Simi Valley homes built before 1980, spaced sheathing is common, and skipping resheathing voids the wind warranty and invites blow-offs during Santa Ana events. We tell homeowners this before the estimate, not as a surprise change order.
Owens Corning Models & Products We Service in Simi Valley
We install and repair the full Owens Corning residential lineup: Duration Series, Oakridge Series, Supreme Series, and Berkshire Series. When the roof is being replaced, we install genuine Owens Corning shingles with matching Owens Corning hip and ridge, starter, and underlayments. Mixing brands voids the manufacturer’s wind warranty. For repairs on existing Owens Corning roofs, we source factory-match shingles through Owens Corning roofing supply distributors. We use quality aftermarket flashing, vent boots, and sealants that meet or exceed code where appropriate, and we recommend replacement when the remaining shingle lifespan is under ten years. If you’re in the Simi Valley service area, we’ll tell you straight which path makes sense for your roof.
See the difference
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AfterOwens Corning Service Pricing in Simi Valley
What does Owens Corning roofing service cost in Simi Valley? Here are the ranges we quote most often:
- Leak repair: $350-$800 depending on location and severity. Valley repairs run higher because they involve new flashing and underlayment work.
- Shingle replacement (repair): $450-$1,000 for a typical slope section, based on the number of shingles replaced and slope accessibility.
- Partial re-roof (one or two slopes): $3,500-$8,000 depending on square footage, tear-off requirements, and whether resheathing is needed.
- Full re-roof with Duration shingles: $12,000-$22,000 for most Simi Valley tract homes, higher for hillside custom builds with steeper slopes. Resheathing adds $1.50-$2.50 per square foot.
What drives the cost? Square footage, pitch, whether spaced sheathing needs replacing, and the specific Owens Corning line you choose. Duration costs more than Supreme, and Berkshire costs more than both. Every estimate we write in Simi Valley includes a written line-item price before any work starts. Call (341) 217-2677 and we’ll walk you through exactly what your roof needs.
Serving Simi Valley, CA - Our Local Coverage Area
We’re based in the Simi Valley 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 Simi Valley
Duration shingles carry a 130 mph wind warranty when installed with the correct number of nails in the nail strip and proper starter and hip/ridge components. In Simi Valley, the bigger issue is not the shingle itself but the decking underneath. Homes with original spaced sheathing need resheathing before Duration goes on, or the warranty is void and the shingles can lift during Santa Ana events. Call (341) 217-2677 to have us check your deck condition before you commit to a re-roof.
Deck Defense is rated for limited UV exposure, not prolonged direct sunlight. If it sits uncovered for weeks during a Simi Valley summer, the side laps can break down and leak at transitions. We schedule tear-off and installation in sequence to keep exposure time minimal, and if underlayment has been compromised on a stalled job, we replace it before shingles go on.
It depends on the remaining life of the shingle and the leak source. If the Oakridge shingles still have structural life and the leak is localized, a patch with factory-match shingles and new flashing is often the right call. If the shingles have lost most of their granule surface or the decking beneath is compromised, replacement is the honest answer. We’ll write both options with real numbers and let you decide. Estimates are free.
Because the original 1×6 spaced sheathing under your 1960s wood shake cannot support Owens Corning Deck Defense or meet current code and Owens Corning installation requirements. Putting Duration shingles over spaced sheathing voids the wind warranty and leaves you exposed during Santa Ana winds. Resheathing with 7/16 OSB or plywood is a necessary step, and we include it in the written estimate so you see the real cost before work starts.
Yes. Owens Corning Duration and Oakridge shingles are Class A fire-rated when installed with the appropriate underlayment and deck assembly. For hillside homes in Simi Valley’s wildfire risk zones, we recommend Duration because the thicker construction and nail strip design hold up better under both fire exposure and wind. Call (341) 217-2677 for a written quote on a Class A Owens Corning re-roof.
Service Areas Near Simi Valley
We serve Simi Valley and surrounding communities including Woodland Hills, Agoura Hills, West Hills, and Winnetka. For Owens Corning work in neighboring areas, see Owens Corning service in Agoura Hills or Owens Corning service in Woodland Hills.
Book Your Owens Corning Service in Simi Valley Today
A roof should be the last thing you worry about. Let’s make sure it is. Call (341) 217-2677 to schedule your free Owens Corning roofing estimate in Simi Valley. A live person answers, 24/7, and you’ll get a written price before any work begins.
Written by Grant Whitlock, Owner at Mercer Roofing Co Woodland Hills, serving Simi Valley since 2000.