The hidden cause of major roof leaks. We find and fix failed seams before they cause extensive water damage.
Most commercial flat roofs are made up of multiple sheets of membrane material that are joined together at seams. These seams are heat-welded (TPO, PVC) or glued (EPDM) to create a watertight surface. When seams fail—whether from poor installation, age, or stress—water infiltrates at these vulnerable points.
Seam failures are particularly problematic because they can be hard to detect. The gap may be small, hidden beneath the surface, or water may travel along the roof system before showing up inside the building. By the time you see a water stain, significant damage may have already occurred.
Different seam problems require different repair approaches
The most common installation defect. Occurs when welding temperature is too low, leaving a weak bond that separates over time. May look fine initially but fails within a few years.
Dirt, dust, oil, or moisture on the membrane surface prevents proper bonding. The weld looks complete but never actually adhered properly.
Thermal cycling causes the membrane to expand and contract repeatedly. Over time, this stress breaks the bond at seams, especially on roof-to-wall transitions.
Self-adhering seam tapes can delaminate as the adhesive dries out. Common on EPDM roofs with tape-seamed systems. Edges lift and curl, allowing water under.
We physically test seam strength by lifting edges and visually inspect all seams throughout the roof. We identify both obvious failures and weakened areas at risk.
For TPO and PVC membranes, we re-weld failed seams using proper temperature and technique. We ensure the new weld is strong and watertight.
For extensively failed seam areas, we may install a reinforced overlay system that covers the failing seams with a new, properly welded membrane layer.
We document all seam failures and repairs with photos, providing you with a complete record of the roof's condition and work performed.
Open seams are one of the most common causes of commercial roof leaks. Get your seams inspected today.