Most facility managers can describe the ritual. The storm passes, the ceiling tile darkens, a contractor climbs up and seals the seam closest to the stain, and the invoice gets paid. Then the next front rolls through and the bucket goes back on the floor. Each round costs money, and each round gives wet insulation, softening deck boards, and mold a little more time to work undisturbed. The reason the patch keeps failing is simple: on low-slope roofing, the entry point is almo