Roof Drain Layout

The sizing of roof drains must be large enough to quickly carry away all water entering the roof drains.

Roof drain layout.

There are three types of drain systems on a flat roof. The next step is to determine each roof area that will be served by a separate leader drain pipe scupper or downspout. Install a drain at most 50 ft. Factors which affect proper roof drainage are deck slope drain size and placement of drains.

Install a drain at most 50 ft. Roof drains zurn plumbing products groupspecification drainage operation 1801 pittsburgh avenue erie pa 16502 phone 814 455 0921 fax. Sizing a roof water drain the first step in sizing a roof drain is to calculate the surface area of the roof that the drains will be covering as well as the average hourly rainfall rate at the building location. From a roof edge.

The full flow capacity of a drain is not realized until the water reaches approximately 2 5 above the inlet in a four inch drain and 3 5 in a six inch drain. The roof is sloped towards the drain through either tapered insulation or through joist modifications below the roofline. Limit roof area to 25 000 sq. From the edge of a valley.

This form of roof drainage is preferred if a clean exterior appearance is desired. It is very critical to position drains for maximum effect. General roof drain system guidelines. These will drain to somewhere near the center of the roof and down through the building to underground storm mains or a detention pond.

Most draining systems on flat roofs have a poor design or are not correctly installed.