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Sandra dickson
Flat roof

Hello there,i have just had a new flat roof done recently and it is holding pools of rainwater,is this normal for flat roofs or should it be sloped enought to drain the water off? Thankyou

ed21
Re: Flat roof

Water should never pond for more than a day or so, preferably not at all. Flat roofs in general should have a 1/4" per foot slope, but never less than 1/8".

Mastercarpentry
Re: Flat roof

According to what kind of roofing material was used, some puddling may be acceptable. EDPM rubber fits this category. Ideally there will be enough slope to prevent puddling with any roof, but this is not an ideal world and sometimes practicalities enter the picture forcing you to miss the ideal target. So long as the roof doesn't give problems and the materials used are rated for the situation you should be OK.

Phil

Re: Flat roof

Water should not be able to hold up on the roof as it will keep the roof wet and with time will star to You should have sloped the roof enough that the water drained on its own and not stay there in a puddle.But at times the material used in the construction of the roof is such that it allows puddling for a few days and so i think that you should get information on the kind of material used in the construction of the roof and only then will you find an appropriate answer to your question.

dj1
Re: Flat roof

At this point you have 2 choices: accept your current situation (not good), or re-do your roof, this time with enough slope to allow all water to go down. Puddles on a flat roof is asking for trouble later on.

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