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CertainTeed Roofing in Simi Valley, CA | Mercer Roofing Co Woodland Hills
We’re an independent Simi Valley Roofing Company that tears off, repairs, and installs CertainTeed shingles across Simi Valley, from the flat ranch tracts near Erringer Road to the hillside homes above the 118. We’re not a CertainTeed-authorized contractor, and we’ll tell you that straight. What we are is the crew that knows how CertainTeed Landmark and Landmark PRO actually hold up under Simi Valley’s 100-degree summers and Santa Ana gusts. Call (341) 217-2677 for a free estimate with a written price before any work starts.
Why Simi Valley Residents Choose Us for CertainTeed Service
We’ve torn off enough CertainTeed in Simi Valley to know exactly where it fails first here. South-facing slopes get hammered by UV from May through October. Rake edges lift during fall wind events. Valley flashing separates on older ranch homes where the decking was never truly flat to begin with. Grant Whitlock, our owner, grew up in Los Angeles and trained through the construction technology program at Los Angeles Trade-Technical College. He’s been putting roofs on Valley homes for well over a decade, and he’ll tell you when Simi Valley Roof Repair makes sense and when it doesn’t. Before any of our techs show up, you get their name and photo sent to you. They arrive in a marked uniform, badge in with photo ID, and hand you a written price before a single nail goes down. That’s the Threshold Standard, and we’re held to it on every visit.
Styles & brands we work with
Common CertainTeed Roofing Problems We Solve in Simi Valley
- Premature granule loss on south-facing slopes. Simi Valley gets more intense, sustained UV than the coastal cities west of the 23. We regularly see CertainTeed Landmark shingles losing granules 8 to 10 years early on south-facing pitches, which leaves the asphalt mat exposed and accelerates cracking. A granule check takes us under an hour, and if the loss is localized, we can spot-repair before you’re looking at a full reroof.
- Wind uplift at rake edges during Santa Ana events. Those fall gusts that hit 50+ mph in the hills don’t just rattle fences. On gable roofs, especially in older tracts like the Bird Streets off Erringer Road, rake-edge shingles get pried upward and then reseated, which breaks the seal strip. Once that seal fails, the next wind event starts peeling shingles. We use high-wind nailing patterns and inspect rakes after every fall wind season.
- Flashing failures at valley intersections. Valley flashing on ranch-style homes built in the 1960s and 1970s is frequently original, and Simi Valley’s heat expansion cycles work the metal until it cracks or separates at the seams. This is the most common source of interior leaks we find in Simi Valley, and it’s almost always repairable without touching the shingle field.
- Cracking and brittleness at vent boot collars. Rubber collars around plumbing vents get hard and brittle after years of 100-degree heat. We see this all over Simi Valley’s east side. The fix is a new boot, and we’ll use a quality aftermarket piece when it outperforms the OEM collar for less money.
- Decking rot under original wood shake. In neighborhoods where homes still carry their original wood shake from the 1960s and 1970s, we routinely find rot at the eaves and around penetrations. You can’t see it from the ground, but it compromises any new shingle install. A pre-work inspection catches this before it becomes a mid-project surprise.
CertainTeed Service in Simi Valley: What Local Conditions Mean for Your Equipment
Here’s the thing about Simi Valley’s older Bird Streets tract that most roofers don’t flag until it’s too late. Many of those original roofs used wood shake laid over spaced sheathing, which means there are gaps between the decking boards. Building code today requires solid sheathing before any shingle goes down. So if an older CertainTeed reroof is quoted as a simple shingle-over, someone is about to hand you a code violation and a roof that will fail early. Our crew did a full tear-off on a ranch-style home off Erringer Road where the original wood shake sat on spaced sheathing. We resheathed the entire deck, then installed CertainTeed Landmark PRO in Weathered Wood with WinterGuard at the eaves and high-wind nailing patterns. The homeowner had been told by another contractor it was a simple shingle-over, but our pre-work inspection prevented a code violation and premature failure. That resheathing adds real cost and time, and we’d rather you know it before the tear-off begins than after.
CertainTeed Models & Products We Service in Simi Valley
We work on the full CertainTeed residential line: Landmark Series, Landmark PRO, Grand Manor, and Northgate Class IV. Northgate matters in Simi Valley’s wildfire-risk hills, because it carries a Class 4 impact rating and a Class A fire rating. We stock common Landmark colors locally in standard bundles for fast repair turnarounds, and we use genuine CertainTeed shingles with matching accessory components like WinterGuard and SwiftStart whenever they’re available. When a quality aftermarket flashing or underlayment outperforms the CertainTeed piece for less money, we’ll say so and show you the price difference in writing. You can learn more about our broader CertainTeed sales & service here.
See the difference
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AfterCertainTeed Service Pricing in Simi Valley
For CertainTeed work in Simi Valley, here are the ranges we see most often: minor vent boot replacement runs $95 to $220. A valley flashing repair typically lands between $350 and $800 depending on how many layers of existing flashing need to be pulled. Full decking resheathing for a standard ranch, needed on those Bird Streets wood shake homes, generally runs $1,800 to $3,200 depending on square footage and decking condition. A full CertainTeed Landmark reroof on a 1,800-square-foot Simi Valley home usually falls between $14,000 and $19,000, and that includes resheathing where code requires it. These are ballpark figures, not bids. Your free estimate gets you an exact line-item written price before any work starts, and every repair carries a written 365-day guarantee with a free second visit if the fix fails. Call (341) 217-2677 to schedule that estimate.
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 – CertainTeed Roofing in Simi Valley
Spot repair is viable if granule loss is isolated to a few shingles or one section of the slope. If granule loss covers more than about a third of a south-facing slope on a 20-year-old Landmark roof in Simi Valley, you’re likely looking at accelerated aging from UV, and replacement is the honest call. We’ll inspect and tell you which side of that line you’re on, in writing, with photos. Call (341) 217-2677 for a free inspection and written estimate.
For hillside homes exposed to sustained Santa Ana gusts, Landmark PRO is our go-to, and in wildfire-risk zones we recommend Northgate Class IV for its impact and fire ratings. Both get installed with high-wind nailing patterns that exceed standard spec on exposed gable edges. If your roof sits in a Class A fire zone, we’ll confirm the ordinance applies to your property before we quote.
The leak usually isn’t the shingles. It’s the valley flashing underneath, which on Simi Valley ranch homes is often original metal that has cracked from decades of heat expansion. Replacing shingles without addressing the flashing means the leak comes back within a season or two. We inspect valley intersections with a moisture meter before any repair so we’re fixing the actual source, not the symptom.
If your home is in an older tract like the Bird Streets and the original wood shake sits on spaced sheathing, yes, full resheathing is required by current building code before CertainTeed shingles can be installed. Skipping that step is a code violation and creates a roof that fails prematurely. If your sheathing is solid plywood or OSB, you likely only need spot repairs at rotted sections. We’ll determine this during the free estimate so there are no surprised costs mid-project.
We can match the color line exactly, because we order from current CertainTeed color stock. But on roofs that are 10-plus years old, the existing shingles have faded under Simi Valley sun, so a fresh bundle of the same color will read slightly darker until it weathers. We’ll show you samples against your roof in daylight before you commit. For exact pricing on a partial repair, call (341) 217-2677 and we’ll put it in writing.
Service Areas Near Simi Valley
We also run CertainTeed service up and down the 101 corridor. From CertainTeed service in Agoura Hills to CertainTeed service in Woodland Hills, plus West Hills, Winnetka, and Topanga, our crews cover the western Valley. For the full picture, see our Simi Valley service area page.
Book Your CertainTeed 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 CertainTeed estimate in Simi Valley. You’ll get a written price before work begins, and if it’s a repair, a written 365-day guarantee comes with it.
Written by Grant Whitlock, Owner at Mercer Roofing Co Woodland Hills, serving Simi Valley since 2000.