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CertainTeed Shingle Repair: The Los Angeles Owner’s Guide
CertainTeed shingle repair in Los Angeles typically runs $385 to $780 installed, depending on how many shingles failed, whether the underlayment is compromised, and how steep your roof is. We stock CertainTeed-compatible shingles on our trucks along with matching ridge caps and starter strips, so most repairs happen in a single visit. The way most LA homeowners discover a shingle problem is the same: a heavy rain finally exposes a leak near a dormer or valley, or a Santa Ana wind event leaves tabs scattered in the yard. Sometimes it’s a faded patch on the roof where a previous repair used the wrong color lot, and it’s been bugging you for two years.
As an independent roofing contractor, Mercer Roofing Co Los Angeles is not affiliated with CertainTeed. What we are is a local shop that works with their shingles every week, knows which product lines hold up on LA roofs, and keeps the common colors and profiles in stock so you’re not waiting on a special order for a $400 repair.
Which CertainTeed Models This Applies To
The repair approach depends on which CertainTeed line is on your roof. The most common in Los Angeles are the entry-level XT 25, the mid-grade Landmark, and the heavier Landmark Pro and Presidential Shake lines on higher-end homes in places like Sherman Oaks, Hancock Park, and the Palisades. Each has a different thickness and exposure, and matching matters more than most people realize. A Landmark shingle has a dimensional, two-layer profile with a wider shadow line, while an XT 25 is a flat 3-tab. You cannot mix those on a visible roof face without it looking wrong, and the overlap won’t seat properly.
To identify what you have, look at the underside of a torn-off shingle or check the original install paperwork for a color name like “Weathered Wood,” “Charcoal Black,” or “Georgetown Gray.” Those color names are consistent across CertainTeed lots, but there’s a compatibility gotcha that catches people: dye lots drift slightly between manufacturing runs. A shingle made in 2019 and one made in 2025 with the same color name may not match perfectly. On small repairs we’ll hand-select from the bundles we carry to get the closest visual match, and on larger repairs we’ll recommend doing the entire roof plane so the color break lands on a ridge or valley where it reads as intentional. For older CertainTeed lines that have been discontinued, which happens with certain XT colors, we source quality aftermarket equivalents that match the profile and exposure, and we’ll show you the comparison before any work starts.
Styles & brands we work with






Signs Your CertainTeed Shingle Repair Is Failing
- Granule loss is showing in gutters or downspouts. CertainTeed shingles shed ceramic granules as they age, but a rapid buildup of granules in one gutter section usually means the shingles on that specific plane are sun-baked beyond service life. The LA sun is hard on south-facing and west-facing slopes, and we regularly see 20-year warranty shingles looking rough after 12 years on those exposures.
- A tab or full shingle is missing after a wind event. The self-sealing adhesive strip on CertainTeed shingles softens with heat and re-seals, but after enough years the bond weakens. When a Santa Ana blows through at 40-plus miles an hour, that’s when the loose tabs finally let go. One missing tab is a repair. A dozen missing tabs across the same plane is a re-roof conversation.
- You see exposed fasteners or a lifted edge near a flashing point. Flashing transitions at chimneys, skylights, and sidewalls are where water gets in first. If the shingle edge around the flashing is curling or the nails are backing out, water is already working into the decking. This is not a caulk-and-hope situation.
- Dark streaking, moss, or algae is spreading on one section. CertainTeed’s algae-resistant shingle lines do hold up better in damp, shaded sections, but LA homes near the coast or under heavy tree cover still get moss and staining. Once it’s under the shingle edges, the tab seal degrades and you get water intrusion at the nail line.
- You noticed a small leak in the attic after heavy rain, but the ceiling isn’t wet yet. That’s the best-case discovery point. The water has breached the shingle layer but is still being caught by the underlayment, so you have time to fix it before it rots decking and stains drywall. We find these early because the homeowner saw a water mark on the sheathing and called before it spread.
See the difference
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AfterReplacement Cost & What’s Included
For a typical CertainTeed shingle repair in Los Angeles, you’re looking at $385 to $520 for a single penetration or small patch, $520 to $780 for multiple shingle replacements across one slope, and $800 to $1,400 if the repair involves replacing compromised decking or re-flashing a chimney or skylight. What drives the range: the steepness and height of the roof (a two-story Spanish-style home in Highland Park costs more to access than a single-story ranch in Lakewood), the number of shingles being pulled, and whether we’re also replacing felt or synthetic underlayment.
Every quote from Mercer Roofing is a written, line-item price before the work begins. You’ll see the parts cost, the labor, and any disposal fee separately. If we open up the area and find decking damage that wasn’t visible from the surface, we stop and show you before adding a dollar to the invoice. The repair itself is covered by our 365-Day Done Right Promise: if the repair fails within a year, we come back and make it right at no charge.
DIY or Call Us?
Let’s be straight about this one. Shingle replacement on a walkable, low-slope roof with a safe ladder setup is something a careful homeowner can do, and you can absolutely inspect your own roof with binoculars from the ground to find the obvious damage. What goes wrong with DIY CertainTeed repairs is almost always one of three things: you break the seal on neighboring shingles while prying up the damaged one, you nail through the wrong part of the shingle and create a new leak, or you slip on a steep pitch. Most LA homes built in the 1920s through 1960s have roof pitches that are genuinely unsafe to walk without fall protection.
Roof work high off the ground is not worth a broken hip. If you’re not completely comfortable on a ladder, call us at (213) 521-8272 and we’ll send a background-checked, photo-badged technician to handle it. You’ll see their name and photo before they arrive, and the price will be in writing before any work starts.
FAQs
CertainTeed shingles in LA typically last 18 to 25 years, not the 30 or 50 years printed on the warranty. The sun load, temp swings, and occasional wind events burn through any asphalt shingle faster than the manufacturer’s ideal-condition number, and we adjust our recommendations accordingly.
Yes, isolated shingle damage can be repaired without re-roofing, provided the decking underneath is sound and the surrounding shingles still have life in them. The threshold is usually around 15 to 20 percent of total shingle damage; beyond that, patching becomes costlier per year of service than a new roof.
A straightforward CertainTeed shingle repair takes 1 to 2 hours on site, plus setup and safety time. Most single-penetration repairs are wrapped up in one visit, and we clean up every nail and scrap before we leave.
We stock the most common CertainTeed profiles and colors in our Los Angeles shop, including Landmark and XT 25 lines in the black, gray, and wood-tone colors that dominate this market. If your color is unusual or discontinued, we’ll source the closest match and give you the price before you commit.
Written by Grant Whitlock, Owner, Mercer Roofing Co at Mercer Roofing Co Los Angeles, serving Los Angeles and nearby areas.