How To Size Roof Leader Collection Pipe Size

Size vertical storm drainage piping.

How to size roof leader collection pipe size.

1106 3 vertical leader sizing vertical leaders shall be sized based on the flow rate from horizontal gutters or the maximum flow rate through roof drains. When sizing roof drains the limiting factor for the amount of water each drain will carry away is the size of leader therefore increasing leader size decreases the number of drains required. Determine 100 year 1 hour rainfall rate used for location of building. Four steps to sizing roof drains.

2 total area of roof. Size horizontal storm drainage piping. Step by step sizing of zurn drains. What size of leader will be required to drain a roof 75 feet long by 50 feet wide.

Table 1106 2 storm drain pipe sizing for si. Roof area is 300 x 500 ft. 75x50 solution 15 square inches and from table vi it is found that a 4 1 2 inch pipe has an area slightly greater than 15 inches. The next step is to determine each roof area that will be served by a separate leader drain pipe scupper or downspout.

When sizing roof drains the limiting factor for the amount of water each drain will carry away is the size of leader therefore increasing leader size decreases the number of drains required. 1 rate of precipitation. 1 inch 25 4 mm 1 foot 304 8 mm 1 gallon per minute 3 785 l m. Step by step sizing of zurn drains step 1.

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. Select number of roof drains and calculate the roof area sloped to each drain. Calculate total roof area.