Water Drainage - Roof Pitch Requirement

RusRoofingAdmin

Good day guys, I am from a Russian based building company and we came accross with a certain problem while working with a flat roof. we are installing an inverted roofing system on a flat roof with 0% pitch - can you share how you create (build) a pitch slope to drain excess of water and what is desirable % of this pitch. Big thank you in advance. Angela

RidgeWalker

http://www.houstonfoam.com/pdf/TaperedRoof.pdf here's who it works.

Ed the Roofer

You need a minimum of a 1/8" per foot slope, but a 1/4" per foot slope would be more effective.

There are many manufacturers of tapered insulation systems to get detailed layout drawings from.

But you already stated that this is a 0 % slope and an IRMA, Inverted Roof Membrane Application, which means that the insulation blocks will be going down on top of the roof membrane and then ballasted on top of that, didn't you?

If that is correct, the tapered insulation system needs to be applied prior to the roof membrane being installed.

Ed