Ipc Roof Drain Sizing

Size horizontal storm drainage piping.

Ipc roof drain sizing.

2 500 4 x 3 75 2 344 sq ft. The flow rate used for sizing the storm drainage piping shall be based on the maximum anticipated ponding on the roof. Section 1105 roof drains 1105 2 roof drain flow rate. Scuppers shall not have an opening dimension of less than 4 inches.

50 000 4 400 11 36. The roof drain typically will not remove the water as fast as you may think. The result is a roof collapse. 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.

When scuppers are used for secondary emergency overflow roof drainage the quantity size location and inlet elevation of the scuppers shall be sized to prevent the depth of ponding water from exceeding that for which the roof was designed as determined by section 1611 1. The result is the number of drains needed. Ipc provides four steps to size the roof drains on a building. Select number of roof drains and calculate the roof area sloped to each drain.

Smacna s new downspout and gutter sizing calculator enables the user to manually enter the design area of the roof or use the design area wizard for the calculation. Each vertical drain must carry 2 500 sq ft of roof area at 3 75 inches per hour of rainfall. The flow through the primary system shall not be considered when locating and sizing secondary scuppers. 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.

Using tools from the international plumbing code ipc it s not that hard. This wizard makes it easy to calculate the roof design area by providing various shape calculations and the calculation for vertical walls area per international plumbing code ipc. From figure 1108 4 the 100 year 60 minute precipitation is 3 75 inches per hour. For example a 4 in.

Example roof plan 4 a 101 2 solution. Sizing vertical roof drains with 2018 international plumbing code. Following this logic it is possible that for roof drains 6 in. Take the roof s total square footage and divide by the total square footage handled by one drain.

Or 12 drains required. Or less in diameter the piping will be larger in diameter than the roof drain. Scupper openings shall be not less than 4 inches 102 mm in height and have a width that is equal to or greater than the circumference of a roof drain sized for the same roof area. To convert to an area for a 4 inch per hour rainfall to enter table 1108 1 do this.