Commercial Roof Leak Repair
A stain that shows up far from any open seam calls for leak tracing before the flat roof patch goes down.
Commercial roof leak repairTPO · EPDM · Mod Bit · Built-Up
Tempe Flat Roof Repair
Flat roof repair in Tempe means fixing the damaged section with the same material the roof already has, after testing whether a sun-baked sheet still takes a weld.
- Four Membrane TypesTPO, EPDM, mod bit, built-up
- Bond Test FirstOld sheet checked before patching
- Drains ClearedDust and debris pulled out
- Photo RecordMarked-up photos afterward
Fix This Section Or Budget For A New Flat Roof?
Flat roofs fail at details, which repair well, or across the whole field, which points to replacement. The roof walk sorts out which one you have.
Repair Holds When
- Leaks trace to seams, drains, curbs, or parapet flashing
- A test weld or adhered patch bonds to the old sheet
- Wet insulation stays inside one marked area
- Ponding sits in one low spot by a drain
- Blisters are few and scattered
Replacement Wins When
- Blisters spread across the whole field
- The sheet cracks when folded or probed
- Core cuts find wet layers in many places
- Two or more re-covers already sit on the deck
- Membrane edges have shrunk away from the walls
Common Leak Points On A Flat Roof
These six details are where flat roof leaks usually start in Tempe, and each one has its own repair.
Open TPO Seams
Heat-welded laps can let go after years of expansion and contraction. A probe run along the seam finds the gap, and a fresh hot-air weld or a cover strip closes it. Seams near curbs and drains get the closest look, since water sits there longest.
Blisters In The Field
Trapped moisture or air lifts the membrane into soft bubbles that split under foot traffic. We cut them out, dry the spot, and patch with matching sheet. A blister that has not split yet still gets cut out, because foot traffic will open it.
Ponding Rings By Drains
Low spots around a drain hold water for days and leave a dirt ring. Clearing the strainer comes first; a spot that still holds water gets tapered insulation. If the drain bowl sits above the field, it gets reset lower so water reaches the strainer.
Parapet Base Flashing
Flashing that climbs the wall dries out and pulls away at its top edge. It gets rebuilt with new sheet, a termination bar, and fresh sealant at the joint. Counterflashing or a metal cap goes over the top edge so sun and rain stay off the seal.
Curb Corners
Inside and outside corners at rooftop unit curbs crack first because the sheet folds there. Prefabricated corners or hand-formed patches seal them back up. On TPO the corners get welded; on EPDM they get pressure-sensitive corner flashing pieces.
Bare Spots On Gravel Roofs
Where gravel has washed or blown off a built-up roof, sun dries the bitumen until it cracks. We patch the plies and set fresh gravel over the repair. Fresh gravel also keeps sun off the bitumen, which is what dried out the plies in the first place.
Flat Roof Repair Work We Do In Tempe
Each repair matches the roof system already on the building, so the patch moves with the sheet around it.
| Roof System | Common Failure | Repair We Make |
|---|---|---|
| TPO | Open welds at laps and curb corners | Clean the sheet, then re-weld with hot air or weld on a cover strip |
| EPDM | Seam tape letting go, shrinkage at the edges | Seam primer and new tape, with cover tape along shrunken edges |
| Modified bitumen | Cracked cap sheet and open laps | Cut back to firm sheet and patch with matching cap sheet |
| Built-up gravel | Bare spots and blisters between plies | Scrape the gravel, patch the plies, and re-embed gravel |
| Any flat system | Dried parapet and pipe flashing | Rebuild the flashing and reset pitch pans and pipe boots |
What Fixing It Now Protects
Flat roofs hold water longer than sloped ones, so a small opening soaks more insulation with every storm it stays open.
- Insulation boards around the opening, before they turn soft and crush
- Drain bowls and deck metal sitting under standing water
- Ceiling tile and light fixtures in the suites below
- Curb flashing under units your HVAC contractor services
- Older membrane that keeps working once its details are sealed
Ponding Ring Getting Wider?
Call with how many days water stands after a storm and whether you can see the drain strainer. Clearing a packed drain is often the first fix.
How A Flat Roof Repair Runs
Five steps, from the first moisture reading to the photos you keep for your maintenance file.
Inspect Your Roof
A moisture meter runs across the field and around every curb, drain, and parapet. Any reading above the dry baseline gets marked for a core cut. Core cuts get patched before the crew leaves the roof.
On The Roof
Mark Every Entry Point
Open welds are probed, blisters pressed, and pitch pans checked for shrinkage. Each problem gets a number on a roof sketch and a photo. You see the numbered list before any repair is priced.
On The RoofProtect The Space Below
Tenants under the work area get a heads-up, and sheeting goes over anything wet or sensitive before the crew cuts into the membrane. Rooftop units stay running unless their curb is the one being repaired.
At The BuildingRepair With Matching Material
Test patches show whether the old sheet still bonds. Then wet insulation comes out, new boards go in, and new sheet is welded, taped, or set in place. Every patch extends past the damage onto firm, clean sheet.
On The Roof
Water-Test And Hand Over Photos
Seams get probed again once they cool, and drains get a flow check. You keep the numbered sketch with photos of each repair. The sketch also flags details that are aging but still holding.
Paperwork
Related Repairs For Flat Roofs
Flat roof work often overlaps with these two services.
Industrial Roof Repair
Plant roofs with exhaust fans and process vents need residue cleanup and production-aware scheduling around the patch.
Industrial roof repairFlat Roof Questions From Tempe Owners
Answers about the repair itself, drainage, and the different flat roof materials.
The Repair
What does flat roof repair in Tempe involve?
Matching what is already up there. The crew identifies the sheet (TPO, EPDM, modified bitumen, or built-up gravel), then tests a small weld or patch to see whether sun-baked membrane still bonds before repairing the failed section.
On most Tempe flat roofs that means re-welding seams, cutting out blisters, rebuilding parapet flashing, or fixing a low spot where a ponding ring keeps forming by a drain.
The Repair
Can a new patch go over an old patch?
Rarely well. Each layer of mastic or tape bonds only to what sits under it, so old patches get cut back to clean membrane and the repair starts from there.
The Repair
How big is a typical flat roof patch?
Big enough to reach firm, dry sheet on every side of the damage. Small punctures get a patch a few inches past the hole, while a blister or wet spot gets cut back to dry insulation, which is often much larger than the stain inside suggested.
Drainage
Why does water stand around my roof drains?
Usually a dust-packed strainer, a drain bowl set high, or insulation that has compressed around the drain. Clearing the drain comes first, and a low spot that still holds water gets tapered insulation.
Drainage
Is ponding water the same thing as a leak?
Ponding is standing water on top of the roof. It becomes a leak once a seam, blister, or old patch inside the wet area opens, and water sitting for days makes that more likely.
Materials
Can TPO be welded to EPDM?
No. The two sheets use different chemistry, so a transition between them needs a compatible tape or a separate flashing detail, and each side gets repaired with its own material.
Materials
Can modified bitumen be repaired without a torch?
Yes. Cold-applied adhesive and self-adhered cap sheet handle most modified bitumen patches, which keeps open flame away from vents, intakes, and stored materials near the roof.
Get The Flat Roof Opening Closed
Tell us the roof type if you know it and where water shows inside. We will walk the roof and mark what needs repair.