Location of drains 5.
Roof drainage design guide.
Inspect the current roof drain s and the drain line through the building for leaks and assure that the materials are.
In the design and detailing of a roof drainage system consideration must be given to a range of factors such as.
The location and degree to which.
Design assistance services are offered as a courtesy to the roofing design professional and contractors to ensure the project s success.
Developing the design criteria for a roof drainage plan that will perform with the roofing system to drain the roof is critical priorto the bid process and roof system installation.
Size vertical storm drainage piping.
Determine leader or pipe size.
The greater the slope the less water build up and thus roof load.
2 3 4 5 6.
Roofs inevitably serve as temporary rainwater reservoirs.
To select the proper roof drain the following information must be known.
The sizing of the roof drainage system must consider all components.
Calculate the total roof area by multiplying its length by width.
Secondary drainage shall be provided through the use of sidewall scuppers or internal roof drains.
In either case the discharge shall be located so that it is readily visible by building occupants.
Structural design of the roof and roof load.
Select number of roof drains and calculate the roof area sloped to each drain.
Step by step instructions step 1.
When selecting a roof drain note.
Volume of expected rainfall.
Desired rate of drainage 6.
From there consider the following.
Determine 100 year 1 hour rainfall rate used for location of building.
Rainfall intensity roof catchment area gutter size capacity gutter fall gutter outlets sumps rain heads nozzles downpipe size quantity and placement overflow consideration material.
Roof load requirement 7.
First and foremost be sure to comply with all local plumbing codes.
Secondary or emergency roof drainage is required wherever the buildup of water is detrimental to the roof structure.
Type of roof construction 2.
Calculate total roof area.
Properly designed roof drain must have the following features.
Maximum pipe flow.
Safety load requirement 8.
Pleasing dome shape with a low profile and adequate free drainage area corrosion resisting dome material effective debris protection overflow drainage to allow drainage during debris build up gravel stop positive flashing clamp seepage control channels.
Ipc provides four steps to size the roof drains on a building.
Slope of the roof.
Size horizontal storm drainage piping.
