Drain size for flat roof

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Joined: Thu Oct 22, 2015 6:27 am

Drain size for flat roof

Post by phantomvs » Fri Feb 08, 2019 4:56 am

I plan on adding an extra drain on my flat roof.
Presently I only have one and I find it's not enough. It's at the edge of roof .
Water tends to puddle in the middle not much slope on this roof.
I was thinking of adding another one to the center of roof.
Sincerely I plan on redoing roof it would be easier to slope all water there.
My question is a 2" abs drain pipe ok ? Or is there another type to use.
Does it need to be insulated ?

Thanks is !

Posts: 183
Joined: Mon Mar 27, 2017 9:15 am

Re: Drain size for flat roof

Post by Clarence » Fri Feb 08, 2019 6:42 am

You need to calculate the roof area & rain fall for your area to get the correct size drain pipe. Research Roof drain Calculation it will help you figure the correct material.

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