How far does the seam failure extend?
We locate the beginning and end of the visibly open area, then examine adjacent intersections, laps, patches and changes in membrane direction. A short skip at a joint can be different from a long area of poor adhesion or a seam affected by movement at a curb. We compare the outside appearance with the underside only where the assembly is accessible or an opening is authorized. The scope should state what was examined and whether concealed layers remain unknown. The membrane identification controls whether a TPO roofing system repair method is appropriate for this lap.
If water has appeared inside, record the timing and room rather than assuming it entered through the nearest visible seam. Roof assemblies can move water laterally before it appears. A seam may need repair even when it is not the source of a reported leak, while the actual entry may be at a drain, flashing or penetration. A useful investigation keeps the visible defect, reported symptom and proposed repair connected without treating them as interchangeable proof. PVC roofing system repair requires confirming that the sheet and proposed welding materials belong together.
