Can a leaking flat rubber roof be repaired?

It can be done, but it is not easy or certain. The roofer you contacted probably warranties his/her work to be done once and done right, so that their warranty is moot. Patching, even if you do know where the leak is, is a tricky business of laminating on a new piece of roofing membrane, making sure all your flashing is tight and well-sealed, and then waiting for rain (indoors and out). If it still rains inside, repeat. This is not a process a contractor wants to start. If you want to take something like this on yourself, bring patience and more money than you think you need. Good luck!

Is the roof pitched or flat? If there is any pitch at all, a coating with KoolSeal will probably fix it. If it's flat with minor high & low spots that catch water you might want to consider getting it modified so that it will drain. Water laying in a pool will eventually find its way through. Kool Seal has several products depending on your situation. If it's going on a rubber roof it'll need a primer coat. Don't skip that. Read the directions. It's important if you want it to last.

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