Flat Roof Deck Drainage

First mark all the purlin locations on the deck joists.

Flat roof deck drainage.

For flat roof drainage where you place your drains scuppers and the final material of the roofing is more important. The angle is not significant enough to prevent water from pooling on the surface. At page top and at left our photos show a low slope roof surrounded by a parapet. If the span under your deck is 12 ft for example the purlin at the outer end of the deck should be 3 in.

Roof drains watts roof drains provide flexible solutions for specifiers and installers in any commercial roof application. Roofs of this design will have one or more roof drains or scuppers installed. The slope takes water to the drains. Removing ponding water or puddles on a flat roof can easily be done by installing a 12 shower drain from home depot.

It was more like seepage and so in roof decks and balconies the roofers introduced a drainage gap. The drainage requirements for flat roofs on buildings present some special problems that we describe and illustrate here. The key is in the word flat. When a roof is flat it actually will have a very slight slope water is going to spend a lot more time in one place giving it more time to find a way underneath the roof.

Lower than the purlin along the house 12 x 1 4 3. Gapping the deck boards a minimal of 1 4 is necessary to prevent pooling water on the deck surface and top allow for air to dry the water that does not drain of the roof surface underneath. Of course the best designed flat roof has the correct amount of pitch to drain the water off naturally. To keep damage like leaks from occurring water should not stand on a flat roof for more than 48 hours.

Watch for clogs blockage at the roof drain or scupper. What s the difference between a regular roof and a flat roof and why does it require different material. The roofers recognized that not a lot of drainage occurred in the mortar bed despite the crushed stone around the drain. Our exclusive dual functional structural deck flange and combination roof drains streamline specifications saving installation time and labor.

While the slope of your roof ensures that any water is shedded of the roof surface to the edge of the roof roof drainage makes sure that water gets from the roof surface to the ground. The drains take water to the ground. The most critical of these issues is the flat roof drainage systems. The deck surface should be installed so that proper ventilation and drainage can occur.