Rubber Roof Leaks when snow and water builds up

[CJ]

I have a flat rubber roof that leaks very badly when it snows and then rains. It happened twice this year during two storms between Feb and March. The weight of the snow and rain somehow must pull the rubber away from where it should cover the roof from the outside elements. When it rains hard it never leaks.

There is a vent pipe and a square opening with cover (to gain access) near the leak.

Any ideas on what to do?

CP

[EXT]

To pull the rubber roof, something must be sagging from the weight. You may want to check the framing to see if it needs beefing up. Only other thing could be contraction from the cold but I can't imagine it would contract that much if properly installed.

[tom]

You could go up there and inspect each seam and flashing yourself. If you find some loose spots, you could clean them (thoroughly) and apply rubber or contact cement. Or call a roofer who's experienced with rubber roofs. I'm betting it's one of the protrusions giving you trouble. Start looking there. Tom

[Bob (but not THAT Bob)]

I'd guess it's the square access hole where the problem is located.

The membrane had to be cut and patched to create a curb, and since melting snow is higher than rain alone, it's leaking at a particular level.

Take a look here:

This manual shows how it should have been done, so you'll be able to see what's required to fix it.

Patches, adhesive and such are all available locally, and DIY is easy.

Remember, if a roofer can do it, it sure ain't rocket science.

[<josh]

I&#39;m guessing the leak is always there, but when it just rains, the water ponds lower than the leak and runs away.

When the snow builds up, it elevates the backed-up water so it reaches the leak. Could even be going over the top of the rubber where it runs up on the penetrations.

[rvliquidroof]

Yeah you are right when the snow or rain comes the roof definitely is in danger and needs the immediate response. thanks for sharing.