In this article 16 sections
- How Is a TPO Roof Repaired?
- Most Common TPO Failures (Seams, Flashing, Punctures, Shrinkage)
- Repair Methods | Heat-Welded Patches vs Tapes vs Coatings
- TPO Repair Cost
- Why DIY Patches Can Void Your Warranty
- Signs Your TPO Roof Was Installed Poorly
- When a TPO Roof Needs Replacement Instead
- FAQs | TPO Repair
- Can old TPO be welded?
- How long does a TPO repair last?
- Can I coat a TPO roof instead of repairing it?
- Is TPO tape a permanent repair?
- How do you find a leak in a TPO roof?
- What can I use to patch a TPO roof?
- Can a TPO roof last 30 years?
- Get Your TPO Roof Repaired
How Is a TPO Roof Repaired?
The weld is only as good as the prep. Surface preparation is the most common reason TPO repairs fail. Here’s how we approach TPO work as part of commercial roofing in San Antonio, and what to watch for.
Most Common TPO Failures (Seams, Flashing, Punctures, Shrinkage)
| Failure | What it looks like | Typical cause |
|---|---|---|
| Open or weak seams | Lifted edges, gaps you can probe | Poor original weld, movement, age |
| Flashing failure | Flashing pulling from walls, curbs or edges | Movement, poor detailing, UV |
| Punctures | Holes or cuts near HVAC units and walkways | Dropped tools, foot traffic, hail |
| Shrinkage | Membrane pulling at perimeters and corners | Age and heat cycling |
| Surface cracking | Fine cracks, chalky surface, exposed scrim | UV and heat aging |
Repair Methods | Heat-Welded Patches vs Tapes vs Coatings
| Method | How it works | Best use |
|---|---|---|
| Heat-welded TPO patch | Clean, prime as needed, hot-air weld a TPO patch with rounded corners | Permanent repair of punctures and small damage |
| Seam re-weld | Clean the seam and re-weld, then probe the weld | Open or weak seams |
| Flashing replacement | Remove failed flashing, install new TPO flashing | Walls, curbs, edges, penetrations |
| Repair tape / cover strip | Primed, adhered TPO tape | Where welding isn’t practical; follow manufacturer rules |
| Coating | Silicone or other coating over a cleaned, repaired roof | Restoring an aging but dry TPO roof |
Older, weathered TPO develops surface oxidation that can stop a weld from bonding. It needs more aggressive cleaning and primer, and sometimes a weld test before the repair. Avoid asphalt mastic on TPO: it doesn’t bond and the smeared area usually has to be cut out later.
TPO Repair Cost
| Repair | Typical cost |
|---|---|
| Small TPO patch | $300 – $1,200 |
| TPO repair, per sq ft of repair area | $6 – $10 |
| Seam reseal (50 – 200 linear ft) | $1,800 – $7,500 |
| Curb or penetration re-flash | $500 – $2,500 each |
| Wet insulation replacement (add-on) | $1.50 – $2.00 / sq ft |
SuperSeal Roofing (Apr 2026); The Roofing Brief (2026).
Why DIY Patches Can Void Your Warranty
- Most manufacturer warranties require repairs by an authorized contractor using approved materials.
- Before any repair, notify the warrantor and get approval so the repair stays covered.
- Wrong products, like mastic or tapes not approved for TPO, can contaminate the membrane and force a larger repair.
- Staff should stick to temporary measures and leave permanent repairs to a qualified roofer.
Signs Your TPO Roof Was Installed Poorly
- Peeling, bubbling or lifting sheets, often from a dirty or wet surface at install
- Seams that open early, a sign of poor welding temperature or speed
- Membrane pulling at walls and curbs (shrinkage), leaving gaps at flashings
- Wrinkles and fishmouths at seams
- Missing walk pads around rooftop units
If the roof is still under a workmanship or manufacturer warranty, report these in writing before anyone repairs them.
When a TPO Roof Needs Replacement Instead
- Seam failures over long runs, often more than about 200 linear feet
- Widespread shrinkage, cracking or exposed scrim
- Wet insulation across large areas
- Roof over about 20 years old with repairs piling up
At that point, compare a recover, coating and replacement. See TPO roofing in San Antonio and commercial roof replacement in San Antonio.
FAQs | TPO Repair
Can old TPO be welded?
Often yes, but weathered TPO needs thorough cleaning and primer to remove surface oxidation, and a test weld should confirm it bonds. Very old, brittle TPO may not weld reliably, which is a sign replacement is near.
How long does a TPO repair last?
A properly welded TPO patch on a sound roof can last as long as the rest of the membrane. Repairs on aging, oxidized TPO last less because the surrounding material keeps deteriorating.
Can I coat a TPO roof instead of repairing it?
A coating is applied after repairs, not instead of them. Damaged areas are fixed first, then a compatible primer and coating restore the whole surface if the roof is dry and sound.
Is TPO tape a permanent repair?
Manufacturer-approved TPO repair tape on a properly cleaned and primed surface can be a durable repair in some situations, but heat welding is generally the stronger, preferred method.
How do you find a leak in a TPO roof?
Check seams, flashings and penetrations first, since that’s where most TPO leaks start. Seams are probed for gaps, and moisture testing or electronic leak detection pinpoints harder-to-find breaches.
What can I use to patch a TPO roof?
A permanent repair uses a matching TPO patch, cleaned and primed, then heat-welded. TPO tape or a peel-and-stick patch works as a temporary fix until a roofer can weld it.
Can a TPO roof last 30 years?
Some do, especially thicker 60 to 80 mil membranes that are well installed, drain properly and are maintained. Plan on 20 to 30 years in San Antonio’s heat.
Get Your TPO Roof Repaired
We’ll inspect seams, flashings and penetrations, check for wet insulation, and weld repairs that match your membrane and keep your warranty intact.
- Fast response across San Antonio, including commercial roofing in Stone Oak, Westover Hills and Live Oak
Book your free roof inspection in San Antonio or see commercial roof repair in San Antonio.
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