I have a flat polyurethane foam roof with a blister that was cracked and leaking during the winter. I live in Palm Springs, so usually hot and dry with very little rain.
A foam roofing company told me to cut the top of the blister off until it was flush with the roof, then fill the hole with a good sealant, then cover with roof fabric and elastomeric paint. I sealed it with a high quality acrylic sealant from GAF and no more leaks.
Today I cut off another blister, but the area around it turned out to be bigger than I realized – 2ft x 3ft.
The foam pieces I cut away are in decent condition. No mold or dirt, just a bit warped.
Since the GAF sealant is expensive, I figured I would just put the foam pieces back in place with some good adhesive like liquid nails, then urethane caulk and roof tape on the seams. Finish with an elastomeric top coat and call it a day. Is this good enough?
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