Ponding on rubber roof

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1

Originally Posted By: rkuntz
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Should water pond on a rubber roof. I did a house that had a 10 x 20 flat roof that allowed 3 or 4 inch deep water to lay over most of its surface. I don’t have much experience with rubber roofs so any help would be appriciated.

2

Originally Posted By: Blaine Wiley
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Report it as in need of repair. A one inch pond over a 20 foot roof would weigh about a ton. 4" of water is scary!! icon_eek.gif

3

Originally Posted By: Guest
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180sf (most of the roof) average depth= 1.5 inches …


180x144(to convert to sq inches) =25,920 x 1.5= 38,880 cubic inches divided by 268.8(cubic inches in a gallon)=144.64 gallons x 8.38


(lbs per gallon)= ~1,112 lbs divided by 180 square feet =6.73 lbs per square foot. There’s easier ways to figure that out but I only know certain specs about water.


It'll hold it, but it's far from ideal. Either a roof drain should be installed (or cleaned) or measures should be taken to raise the center of the roof.
It's going to leak and when it does it'll guarantee up to 150 gallons of water inside the structure.

4

Originally Posted By: rkuntz
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Thanks for the reply. That was my thought as well. The roofer will be there tomorrow for further evaluation.

5

Originally Posted By: jane molina
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And to think ponding use to be a plus back in the day for insulation purposes.

6

Originally Posted By: ekartal
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If there are roof drains they may not be flush with the roof.


Erol Kartal