Commercial Roofing
Commercial roof repair in San Jose
A commercial leak costs more than the repair: stock, equipment, a closed room. We find the source on the roof, fix it in the same material, and work around the business below.
What we treat
- Concrete and clay tile
- Composition shingle
- Flat, torch-down and TPO
- Spray foam
- Standing seam metal
Quick answer. Commercial roof repair in San Jose covers welded patches on TPO and PVC, new plies on modified bitumen, spot repairs on built-up and gravel roofs, and rebuilt flashing at HVAC curbs, drains and parapets. Most leaks are traced and repaired in one visit, with a written report and photos for the property manager.
Updated September 2026
The job
Where commercial roofs leak
On low-slope commercial roofs the leaks cluster in the same places: around rooftop units, at drains and scuppers, along parapet walls, and at seams where foot traffic from service techs wears the membrane.
We trace from inside when the ceiling allows it, confirm on the roof, and repair in the existing system so the manufacturer's terms are not complicated by mixed materials.
What happens after you call
How a commercial repair call runs
- 1
Call and access
Who lets us in, where the leak shows, any hatch or key.
- 2
Trace
From the ceiling to the roof above it.
- 3
Repair in kind
Same membrane or system as the roof.
- 4
Check drains
Every drain and scupper looked at.
- 5
Report
Photos, cause and a priced list of other issues.
- 6
Follow-up
Approved items scheduled around the business.
Warning signs
Signs a commercial roof needs attention
- Ceiling tile stains
Water is reaching the plenum.
- Ponding after rain
Drains or slope have a problem.
- Blisters and ridges
Moisture or movement under the membrane.
- Open seams near units
Service traffic has worn the flashing.
- Gravel scoured away
The built-up surface is exposed to the sun.
- Rust at curbs and edges
Metal flashing is failing.
Jobs this page covers
Single-ply membrane repairs
TPO and PVC punctures, split seams and loose flashing are repaired by cleaning the area and hot-air welding new membrane over it. Aged membrane is prepared with a cleaner first so the weld holds. Where a roof is under a manufacturer warranty, we use the same membrane and follow the manufacturer's repair details, and we give you a photo record that can go into the warranty file. Tape-and-sealant patches from earlier repairs are cut out and replaced with welded membrane, since they tend to fail again within a season.
Built-up and gravel roof repairs
On built-up roofs we scrape back the gravel, cut out cracked or blistered felts, and rebuild the plies with new felt and bitumen before re-embedding gravel in a fresh flood coat so the sun cannot reach the new plies. Alligatored surfaces and splits along the deck joints are the common failures. Where a built-up roof has wet insulation over a large area, spot repairs will not hold for long, and we say so with the moisture readings to back it up.
Drain and scupper clearing
A blocked drain turns the whole roof into a pond, and the weight and standing water find every weak seam. We clear drains, scuppers and leaders, replace missing strainers and clamping rings, and check that overflow scuppers are open. Where drains sit higher than the roof around them, we build up the low areas so water actually reaches them. Clearing drains before winter is the cheapest leak prevention a commercial roof gets. Strainers are checked every visit, because a missing one lets debris straight into the leader.
HVAC curb and penetration leaks
Rooftop units, exhaust fans and conduit penetrations each break the membrane, and their flashing takes the most abuse from service calls. We rebuild curb flashing, reseal pitch pans with new filler and hood them where possible, and add walk pads along the paths service techs use. When a leak traces to an equipment seal rather than the roof, we tell you which trade to call instead of patching around it. Condensate lines draining onto the membrane are rerouted to a drain, since constant water on one spot wears it through.
What we see on San Jose roofs
Roofing labor in San Jose runs around $94 an hour, above the national average, which shapes how we plan commercial repairs. Tracing a leak properly the first time, and repairing every weak detail found on the same visit, is cheaper than return trips. That is why commercial calls end with a written list of everything else we saw on the roof, priced, so the property manager can approve it while the crew is still up there.
Timeline
How long a repair keeps a space out of use
Most single-leak repairs take a few hours on the roof and nothing inside beyond moving a ceiling tile. Where tenants cannot have noise or roof traffic during business hours, we schedule early mornings, evenings or weekends and tell you up front if that changes the price.
Cost
What commercial repairs cost depend on
Repairs are priced by system, extent and access, with a written scope before work beyond the leak itself.
- Roof system Single-ply, built-up and modified bitumen use different crews.
- Leak location Curbs and drains take more detail work than open field.
- Wet insulation Soaked boards under the leak are replaced.
- Access Roof hatches, ladders and lifts for materials.
- After-hours work Night or weekend repairs to avoid disrupting tenants.
- Documentation Reports for property managers and warranty files.
Brands we install and service
FAQ
Questions we get asked
Yes, and we schedule around the business where needed.
Not when it uses the same system and follows the manufacturer's details. We document it for the warranty file.
Yes. See our commercial roof maintenance service for scheduled inspections and reports.
Yes, including multifamily, retail and office roofs.
When wet insulation covers large areas or repairs keep failing. We show you the readings.
Same category
Related roofing work
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TPO and PVC installs and recovers scheduled around tenants.
Learn moreRoof Coating
Silicone and acrylic coatings that extend a sound flat or metal roof.
Learn moreCommercial Roof Maintenance
Scheduled inspections, drain service and written reports.
Learn moreHOA & Multifamily Roofing
Condo, townhome and apartment roofs, bid and phased for boards and managers.
Learn moreLeak in the building? Call now
Tell us the roof type if you know it and where the water shows. We answer any hour and work around your tenants.