Metal roofing
Architectural shingles
Tile roofing
GAF
Owens Corning
Flat & low-slopeFree roof inspection with deck photos before we talk money - GAF and Owens Corning certified installation
Fast, Reliable Roof Replacement Across San Gabriel
Roof replacement in San Gabriel usually runs $11,000 to $24,000 for a typical single-story ranch or Spanish-style stucco home, depending on the roof’s square footage, tear-off layers, and whether the property includes detached structures. Most full replacements here take four to seven working days once materials are staged. Seacrest Roofing serves every ZIP in San Gabriel, 91775, 91776, and 91778, with crews that know the difference between a Mission-era flat roof and a 1960s wood-shake pitch. Call (855) 597-2817 and we’ll walk the roof with you before any quote is written.
Why Seacrest Roofing Is San Gabriel’s Preferred Roof Replacement Company
San Gabriel homeowners tend to ask better questions than most. They want to know why one shingle line costs more than another, which wind rating their street actually needs, and whether their detached garage can be re-roofed under the same permit. We answer those questions directly because Noel Chambers built Seacrest Roofing around a material-neutral inspection process that diagnoses first and sells second.
Our crews know the streets off San Gabriel Boulevard, the ranch blocks along Alhambra Road, and the foothill-adjacent properties where Santa Ana winds hit harder. We stock shingle bundles locally for San Gabriel jobs and stage materials with smaller lifts on acreage lots so we do not chew up grading or landscaping. San Gabriel customers consistently tell us the difference is that we show them seven brands and an honest recommendation, not a one-brand pitch.
Seacrest Roofing is authorized to install across GAF, CertainTeed, Owens Corning, IKO, Atlas, Tamko, and Boral. That breadth matters in San Gabriel specifically, because HOA requirements in some pockets of the city call for specific color lines or fire-rated assemblies, and a single-line dealer will simply tell you what they carry. We carry the full lineup.
Inspection, repair, and full Roof Replacement are handled in-house. That means the person who finds the problem and the crew who fixes it answer to the same supervisor. No gap between who scoped it and who shows up with the tear-off crew.
Styles & brands we work with






Flat Roof Replacement in San Gabriel
Flat Roof Replacement in San Gabriel is a common job on Spanish-style stucco homes and postwar additions that were built with low-slope built-up roofs or aging modified bitumen. A typical flat roof replacement on a San Gabriel home runs $9,000 to $18,000 depending on square footage, number of penetrations, and the underlayment system specified for the city’s fire-conscious foothill corridor.
Flat roofs do not shed water the way a pitched roof does, so the details matter: drain locations, scupper flashing, roof-to-wall junctions, and the slope correction needed when years of San Gabriel Valley heat have settled a section into a ponding low spot. We scope every penetration before quoting because that is where the real cost lives.
Built-Up and Modified Bitumen
Many San Gabriel flat roofs from the 1960s and 1970s are built-up systems with gravel surfacing that have simply aged out. We tear off to decking, inspect the substrate, and install a modern multi-ply system that meets current fire-rated assembly standards. The decking inspection matters here because decades of dry heat can bake out the original plywood fasteners.
Drainage and Ponding
On open lots where water sheds onto ungraded ground, a flat roof that ponds near the drip edge backs water under the flashing and into the soffit. We correct slope with tapered insulation or a lightweight fill before laying the membrane. In San Gabriel we see this on flat-roof additions where the original drain line was never tied into the lot’s grade.
Roof Installation in San Gabriel
Roof Installation in San Gabriel covers both full tear-off and replacement on existing homes and new roof systems on additions, detached ADUs, and outbuildings. A new roof installation on a detached shop or ADU in San Gabriel typically runs $7,500 to $14,000, and when tied into a main-house re-roof it is usually scoped under the same permit package rather than pulled separately.
Before quoting any installation we map every roofed square on the property. Main house, detached garage, shop, ADU, covered patio, even a pergola if it is tied to the roof structure. In San Gabriel that mapping step matters because many acreage properties have two or three roofed structures, and missing one changes the price and the permit.
New Construction and Additions
If you are adding a room or building a new structure on your San Gabriel property, the roof installation should be scoped before framing is locked. That lets us spec the right decking, underlayment, and nailing pattern from day one, which is cheaper than retrofitting a fire-rated assembly after the fact.
Decking Replacement
On older San Gabriel homes we frequently find decking that looks fine from the attic but crumbles when the first shingle bundle comes off. A decking replacement line item should always be held in the quote as a per-sheet rate, not a vague allowance. We give you the actual number of sheets we think we’ll replace after inspecting the attic and walking the roof.
Trusted Brands We Service in San Gabriel
Seacrest Roofing installs shingles from Owens Corning, IKO, Atlas, and Tamko, among others, but we do not steer you toward whichever box is on the truck. On San Gabriel jobs we stock common colors and profiles locally so tear-off and re-shingle happen in one continuous pull instead of stalling on a backorder. Atlas and Tamko both offer fire-rated architectural lines that fit what the San Gabriel building department expects on foothill-adjacent streets, and IKO’s designer profiles come up often when a homeowner wants a period-appropriate look on a mid-century ranch.
See the difference
Before
After
Before
After
Before
AfterCommon Roof Replacement Problems We See in San Gabriel Homes
- Curled and split wood-shake on west and south slopes. Decades of San Gabriel Valley sun bakes the west and south faces first, and the shake splits along the grain. This often gets misread as a simple shingle swap, but it usually means full decking inspection and a fire-rated assembly are required.
- Ridge cap and tile uplift after Santa Ana winds. On exposed foothill-adjacent streets, wind events lift ridge caps and tiles that were nailed with a starter strip or nailing pattern that never earned the shingle’s wind rating. We trace the failure to the nailing pattern, not just the shingle itself.
- Improper flashing at outbuilding roof-to-wall junctions. On open lots, detached shops and ADUs often shed water onto ungraded ground that backs under the drip edge. The junction where the outbuilding roof meets the wall is the first place we scope on an acreage property.
- Heat-cycled asphalt shingles that granulate and thin. San Gabriel’s dry summers push thermal cycling on aging asphalt shingles harder than most climates. Granule loss on south slopes is a sign the shingle’s asphalt matrix is failing, even if it has not cracked yet.
Pricing for Roof Replacement in San Gabriel, CA
A full roof replacement on a typical San Gabriel home runs $11,000 to $24,000. A flat roof replacement lands between $9,000 and $18,000. A detached ADU or shop roof alone is $7,500 to $14,000 when scoped as its own structure. The biggest price drivers are square footage, tear-off layers, decking replacement, and whether the city requires a fire-rated assembly at your address. We do not bury those costs in a lump sum. Every quote is line-itemed, including the per-sheet decking rate, and we hold that number through the job unless the attic inspection turns up something no one could have known before tear-off. Call (855) 597-2817 for a free estimate.
We Also Serve Cities Near San Gabriel
Seacrest Roofing covers San Gabriel and the surrounding communities, including East San Gabriel, San Marino, Alhambra, and Rosemead. If you are on the border of any of these cities, call us and we will confirm your property’s jurisdiction and permit path before we quote. We keep material staging simple across the SGV corridor.
Serving San Gabriel, CA — Our Local Coverage Area
We’re based in the San Gabriel 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 About Roof Replacement in San Gabriel
Yes. In San Gabriel, a re-roof on an acreage lot with detached shops or ADUs is typically permitted as part of the primary structure’s scope rather than a separate city permit for each outbuilding, so we map every roofed square before quoting to make sure nothing gets left out of the permit or the price. Adding a detached structure usually changes the quote by $7,500 to $14,000 depending on size and condition. Call (855) 597-2817 and we will walk every structure on your property before writing the estimate.
Because San Gabriel sits in a fire-conscious wildland-adjacent foothill corridor with dry Santa Ana winds. The dry season raises ember-resistant assembly concerns even where freeze protection is irrelevant. The building department default in much of the city is a fire-rated underlayment and an ember-resistant assembly on foothill-adjacent streets, and we spec that as the standard rather than an upgrade.
We stage shingle bundles at the curb or the nearest hard surface and shuttle them back with a smaller lift or a material cart on the path we agree on in advance. This keeps the open lot’s grading intact and avoids rutting from a heavy truck. On a recent job off Alhambra Road in the 91775 ZIP, we staged at the curb and shuttled back with a smaller lift to protect the grading while replacing the main house and a detached shop.
Most architectural shingles we install in San Gabriel are rated for 110 to 130 mph uplift when installed with the manufacturer’s nailing pattern and starter strip. The rating only holds if the starter course and nail placement match what the shingle was tested for, which is exactly what we verify on every job. Santa Ana wind events on exposed foothill-adjacent streets are the real test for that rating.
We walk every valley, penetration, chimney, skylight curb, and roof-to-wall junction before we write a number. Valleys get ice and water shield as standard on our San Gabriel jobs because the dry season is followed by short, intense rain events that find any valley that was under-flashed. Penetrations are priced per unit, not buried in a square-foot average. Call (855) 597-2817 and we will put the scope on paper before you commit to anything.
Written by Noel Chambers, Owner at Seacrest Roofing, serving San Gabriel and the San Gabriel Valley since day one.