Following this logic it is possible that for roof drains 6 in.
Ibc roof drain sizing.
2 500 4 x 3 75 2 344 sq ft.
Roof drain vertical requirement for horizontal roof areas at various rainfall rates leader size hourly rainfall in inches pipe open 1 1 1 2 2 2 1 2 3 4 5 6 7 8 size area inches sq.
Take the roof s total square footage and divide by the total square footage handled by one drain.
P 1503 4 roof drainage.
The international codes i codes are the widely accepted comprehensive set of model codes used in the us and abroad to help ensure the engineering of safe sustainable affordable and resilient structures.
Vertical and horizontal storm drain piping shall be sized based on the flow rate through the roof drain.
To convert to an area for a 4 inch per hour rainfall to enter table 1108 1 do this.
Or less in diameter the piping will be larger in diameter than the roof drain.
In total square footage covered per drain 23 14 2 880 1 920 1 440 1 150 960 720 575 480 410 360.
The international code council icc is a non profit organization dedicated to developing model codes and standards used in the design build and compliance process.
P 1503 4 1 secondary emergency overflow drains or scuppers.
Roof drain connected to a 6 in.
The roof drain typically will not remove the water as fast as you may think.
Each 4 drain size in a 6 hourly rainfall area will accommodate drainage of 3 070 sq.
1 inch 25 4 mm 1 inch per foot 83 3 mm m.
The minimum size of any building drain serving a water closet shall be 3 inches.
The result is the number of drains needed.
Or 12 drains required.
From figure 1108 4 the 100 year 60 minute precipitation is 3 75 inches per hour.
For example a 4 in.
Each vertical drain must carry 2 500 sq ft of roof area at 3 75 inches per hour of rainfall.
50 000 4 400 11 36.
According to the chart for 1 8 slope per 12 of pipe for 5 000 square feet of roof area with a 6 per hour of rainfall the required pipe size is 8.
1106 2 size of storm drain piping.
Select a reference of a roof drain size with hourly rainfall together with the roof area square footage you have estimated and then determine from the chart below how many roof drains you require.
The maximum number of drainage fixture units connected to a given size of horizontal branch or vertical soil or waste stack shall be determined using table 710 1 2.
Example roof plan 4 a 101 2 solution.
To size the vertical roof drain for the same parameters 5 000 square feet of room area and 6 per hour of rain consult table 1106 2 figure 3.
Design and installation of roof drainage systems shall comply with section 1503 of this code and sections 1106 and 1108 as applicable of the international plumbing code.
