If Your Roof
Has Seams Lifting or Fishmouthed Along the Laps
A cover strip welded or taped over the open lap closes it, once a probe confirms the boards are dry.
Start WithSeam Repair
Lexington Flat Roof Repair Contractor
Close Open Seams and Split Flashing Before Water Soaks the Insulation
Hire a Lexington flat roof repair contractor for TPO, EPDM, PVC, and modified bitumen roofs with open seams, blisters, punctures, or water that sits after rain.
- Seam Test Welds
- Core Cut Checks
- Drain Work First
MembranesTPO, EPDM, PVC, mod-bit
SeamsWelded or taped to match
PondingDrains cleared, crickets added
MoistureProbed before any patch
Can This Flat Roof Be Fixed With a Repair?
Most problems on a low-slope roof stay repairable while the insulation is dry. Here is how a Lexington flat roof repair contractor sorts the job.
If Your Roof
Shows Soft, Growing Blisters Near Seams or Drains
Those blisters get cut, dried, set back down, and covered with a larger patch.
Start WithBlister Repair
If Your Roof
Holds Water Two Days After Rain
Clearing strainers and resetting drain bowls comes first, then tapered crickets where water sits behind units.
Start WithDrain And Cricket Work
If Your Roof
Has Wet Insulation Spreading Beyond the Leak
A core cut beside the leak shows how far the water went, and wide wet areas move the roof toward restoration or replacement.
Start WithMoisture Survey
Flat Roof Trouble You Can Spot From Inside and Up Top
Low-slope roofs hide damage under the membrane, so the inside clue matters.
Open Lap on a Single-Ply Sheet
Inside The Building
Drips start at a deck seam a few feet from any visible stain.
On The Roof
The seam edge has lifted or fishmouthed, often where sheet shrinkage pulls hardest.
Blister Field Near a Drain
Inside The Building
Ceiling tiles sag in a ring around the drain line below.
On The Roof
Raised, soft bubbles sit between the plies and swell on hot afternoons.
Ponding Behind a Rooftop Unit
Inside The Building
Condensation-looking drips show up only after long, steady rains.
On The Roof
Water sits in the low spot the curb creates and slowly works into the nearest seam.
Split Base Flashing
Inside The Building
Moisture shows along the top of the interior wall under the parapet.
On The Roof
Flashing has pulled away from the parapet face, opening a gap above the membrane.
Flat Roof Repair Options for Lexington
Each repair below matches a method to the membrane already on the roof.
Repairing Open Seams on TPO and EPDM
TPO gets a hot-air welded cover strip after the old sheet is cleaned and test-welded on a scrap. EPDM gets primer and seam tape or a pressure-sensitive strip, and PVC takes a solvent wipe before welding.
Patching a Punctured Roof Membrane
Probing around the hole finds any soaked board, which gets replaced first. Then a round-cornered patch of matching membrane goes on with a few inches of overlap on every side.
Fixing Ponding Water on a Flat Roof
Drain strainers get cleaned, lines get snaked, and bowls that sit high get lowered. Tapered insulation crickets behind units and between drains push the remaining water off.
Blister and Cap Sheet Repair
On built-up and modified bitumen roofs, blisters are cut in an X, dried, and set back in cement or hot asphalt. A new cap sheet strip covers any lap that opened.
Insulation Stays in Place
Repairing a seam while the insulation around it is dry keeps the job to a cover strip. Waiting lets water spread through the boards, and every soaked board has to be cut out before the patch can go on.
- Smaller cut-out areas
- Patches that bond to dry sheet
- Fewer interior stains to clean up
Benefits of Repairing Your Roof
On a flat roof, the dry boards around a leak are worth protecting.
Water Leaves the Roof
Clearing drains and adding crickets moves standing water off before it finds the next weak seam.
Units Keep Running
Most membrane patches go in around rooftop units while they run, with curb flashing work as the exception.
A Plan for the Field
Repeat seam failures in one area show where the sheet is shrinking, which tells you where to budget next.
Water Standing Behind the Rooftop Unit?
Ponding that lasts past two dry days works into the nearest seam. Book a visit and we will clear the drains and check the curb.
Schedule Your Free InspectionHow a Lexington Flat Roof Repair Contractor Works the Job
Five steps take a low-slope repair from the first probe to the final check.
- PROBE
Inspect Your Roof
We walk the membrane around the leak, probe seams and flashing, and check drains before deciding what the repair needs.
- CORE
Check the Insulation
A core cut or meter reading next to the leak shows whether the boards are dry, and soaked boards come out before anything else.
- PREP
Clean and Prime the Sheet
Old membrane gets scrubbed and, for EPDM, primed. Weathered TPO gets a test weld on a scrap to confirm the new strip will bond.
- WELD
Weld, Tape, or Cap
The cover strip, patch, or cap sheet goes on with rounded corners and full overlap, matched to TPO, EPDM, PVC, or modified bitumen.
- CHECK
Probe the Finished Seam
Every new seam gets probed end to end, and photos of the repair go to you with notes on nearby laps.
Other Repair Work on Lexington Roofs
Low-slope buildings often have metal sections, active leaks, or plant equipment too.
Commercial Metal Roof Repair
Metal shop additions beside a membrane roof get their own fastener, lap, and ridge cap repairs.
Typical Repairs
- Stitch screws at opened side laps
- Butyl sealant in end laps
- Skylight panels sealed at each lap
Commercial Roof Leak Repair
When the drip shows up far from any open seam, tracing along the deck finds the real entry point.
Typical Repairs
- Flood tests one area at a time
- Infrared scan of wet insulation
- Pitch pans refilled or replaced
Industrial Roof Repair
Plant roofs with exhaust fans and long seam runs get repairs scheduled around shifts and hot work rules.
Typical Repairs
- Sacrificial pads under grease fans
- Bellows replaced at expansion joints
- Hot work permits for heat welding
Flat Roof Repair Questions From Lexington Owners
These five questions come up on most low-slope roofs.
Which Flat Roof Problems Can Be Repaired Instead of Replaced?
Problems confined to seams, flashing, drains, and small punctures can be repaired as long as the insulation around them is dry. That covers fishmouthed single-ply seams, split flashing at parapets and curbs, hail or tool punctures, loose coping, and cracked drain bowls.
Wet insulation beyond the repair area, a deck sagging between joists, or leaks in many places at once push the roof toward restoration or replacement.
What Is the Repair for an Open Seam on TPO, EPDM, or Modified Bitumen?
Each membrane bonds its own way. TPO and PVC get a hot-air welded cover strip, EPDM gets primer and seam tape or a pressure-sensitive strip, and modified bitumen gets a new cap sheet strip heated or cold-applied over the lap.
Weathered TPO can resist new welds, so a scrap test weld comes first. A seam that reopens beside a repair usually means the whole sheet is shrinking.
Should Blisters on a Flat Roof Be Cut Open or Left Alone?
Small, firm blisters on built-up or modified bitumen are often watched rather than cut. Soft, growing, or cracked blisters, and any near a seam, get cut in an X, dried, set back in cement or hot asphalt, and covered with a larger patch.
Summer heat expands moisture or air trapped between plies. Clusters across a wide area call for a moisture survey before more patches go on.
How Is Ponding Water Fixed on an Existing Flat Roof?
Drains come first: strainers cleaned, lines snaked, and bowls reset if they sit above the membrane. Then tapered crickets go behind rooftop units and between drains, and an added drain or scupper is cut in where the structure allows.
Ponding near a column line or mid-span can mean a deflected deck, which an engineer checks first. Water gone within two days of rain is normal on most low-slope roofs.
How Are Punctures and Torn Membrane Patched?
Start by probing around the hole for wet insulation and replacing any soaked boards. The membrane around the damage is cleaned and prepped, then a round-cornered patch of matching material is welded or taped on with a few inches of overlap all around.
Rounded corners resist peeling. A line of punctures leading to rooftop units shows where walkway pads belong.
Call a Lexington Flat Roof Repair Contractor
Tell us the membrane type and where it leaks. We handle flat roof repair in Lexington, KY, from one open lap to a field of blisters.