We repair failed seams on TPO, EPDM, and PVC roofs across Greater Houston. Seam scans, re-welds, and detail rebuilds that stop leaks on low-slope buildings.

What a Failed Seam Actually Does to a Houston Roof
The seam is where two sheets of single-ply membrane are joined, and on a flat or low-slope roof it is the single most loaded part of the system. Every TPO, PVC, or EPDM roof on a warehouse off Beltway 8 or an office block in Westchase lives or dies by those welds and laps. When a seam opens, water does not stay where it entered. It tracks under the membrane, soaks the insulation, and shows up as a ceiling stain twenty or thirty feet from the actual breach. By the time a tenant reports a drip, the wet insulation has often spread across several roof boards.
We get called for seam failure more than almost any other single-ply problem, and the reason is climate. Houston roofs cycle through long stretches of intense summer heat, then heavy rain events that can dump several inches in an afternoon. That thermal movement works the seams back and forth, season after season, until a weak weld or an aged adhesive lap lets go.
Why Seams Fail Here
Not every seam failure has the same cause, and the repair only holds if we fix the right one. On the buildings we service across Harris County, the failures we see most often come down to a handful of mechanisms.
Heat aging and adhesive breakdown
Older EPDM roofs were assembled with seam tape or liquid adhesive rather than heat welding. Under decades of Gulf Coast sun, those adhesives dry out, lose grip, and the lap edge curls. You can usually lift a failed EPDM seam with a putty knife where it should be fused solid. Once an adhesive seam starts releasing, the failure runs down the lap line because each opened inch puts more peel stress on the next.
Cold welds and dirty welds on single-ply
TPO and PVC seams are hot-air welded, and a weld is only as good as the technician and the conditions on the day it was made. A weld run too cool, too fast, or over a dusty membrane looks closed but never fully fused. These cold welds can pass a casual glance for years, then split open during a thermal cycle or a wind event. Houston dust and the pollen-heavy spring make surface contamination a real factor if the sheet was not cleaned before welding.

Movement and ponding stress

Where a roof holds water after rain, the standing load and the constant wet-dry cycle attack the seams in that low spot first. Combine ponding with the building's own thermal expansion and the seams in a drainage flat get worked harder than anywhere else on the roof. Welds that were never fully fused during the original install

Schedule a roof review

Membrane Seam Failure Repair on Houston Commercial Roofs

Adhesive and tape seams that have aged past their service life

T-joints where three sheets overlap and the center is hard to seal

Seams running through or beside ponding areas

Houston Energy Corridor commercial buildings

Laps that were stretched during installation and are now under constant tension

How We Find Every Open Seam, Not Just the Leaking One

Fixing the one seam above a reported stain is how a roof gets re-leaked the following month. When we come out for seam failure, we evaluate the whole seam network, because a roof that is failing one weld is usually failing others of the same age and the same crew.

Roof planning notes

Roof Scope Notes

Talk with a Houston commercial roofing team

Tracing the leak to its real source

Because water travels laterally between the membrane and the insulation, the stain location is a starting clue and nothing more. We work upslope and across the seam grid from the interior evidence until the probe and the moisture readings agree on where water is actually entering. Only then do we open anything. Our Repair Approach by System

TPO and PVC re-welds

Seam repair is not one method. The membrane type, its age, and how brittle the existing sheet has become all change what will actually bond and last. Talk with a Houston commercial roofing team