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PDaddona 09-13-2011 05:01 PM

Flat Rubber Roof is holding water
Hi. Approximately 9 years ago, I replaced the roof on my house. The house is I think 1959. The roofer at the time suggested we use a rubber roof made from recycled tires for a portion of the roof that is flat. Here the problem is though, over time the roof has become convex just enough to hold water in it after a rain. The water than stands there and only has usual evaporation. The water then starts seeping through the rubber, to the interior painted textured ceiling. The "phantom moisture" becomes steam due to the high temperature in that room, and then pops the texture off of the ceiling. Roofer has gone out of business. Does anyone have any suggestions as to how I make the roof concave so that it does not hold the moisture? Is this something I can do myself? Or should I hire a professional? Any one who has ideas for me I thank you in advance

oldognewtrick 09-13-2011 06:06 PM

Can you post some pics of the area and the membrane that was installed? Rubber roofs don't leach water except through seams, penetrations and laps seams. The problem with trying to patch rubber roofing of this age is that it chalks as it ages and cleaning it to accept sealant is sometimes difficult at best.

The only way to elevate the area that is holding water is to correct this situation when the roof is replaced.

Also, how was the rubber installed, loose laid over the decking or fully adhered to the substrate (glued)?

Oh, one more thing :welcome: to House Repair Talk.

BridgeMan 09-14-2011 03:17 AM

No easy fix, if the problem is in the roof buildup itself, unless you're talking about just a half-inch or so of "dishing" over a short run. You could eliminate that by building up with a heavy course or two of mineral granules application over liquid asphalt.

If that doesn't appear to be the case, and the sag is more significant, you might want to pull a section of sheetrock to determine the size and spacing of joists supporting the roof. An engineer could tell you if your joists are undersized for the span, and possibly suggest viable solutions. The installation of flitch plates comes to mind, glued and screwed to the bottoms of the joists while they are in a pre-cambered condition. It wouldn't be cheap, and would require redoing the entire ceiling under the roof.

chb70 09-17-2011 07:53 PM

Definitely need some pics to see what is happening.

Chicago Roofing

PDaddona 09-26-2011 02:01 PM

Thank you all
Hey there everyone. I wanted to thank you for your answers. I had a roofer to the house, and he said that the flat roof is fine, and should last another 5 - 10 years. So thank you everyone!

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