Roof Leader Sizing

Using figure 8 the 312 g p m.

Roof leader sizing.

But this isn t the whole story. From table a101 2 a 12 inch wide weir with a inch head carries6 460 sq ft. 1 rate of precipitation. The flow rate through vertical leaders shall not exceed that specified in table 1106 3.

3 size of leader required. The above sizing is reflected in the development of figure 4 downspout outlet sizing leader pipe sizing. 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. 2 total area of roof.

Enter table a101 2 to find a length and head that will carry 4 500 sq ft or more. The four things you will need to know are. And 4 area handled by each drain. Use12 ichwdex5 inch high scuppers at four locations.

Vertical leaders shall be sized based on the flow rate from horizontal gutters or the maximum flow rate through roof drains. 2 500 4 x 7 2 9 375 sq ft 4 500 sq ft. 50 000 4 400 11 36. This corresponds to a minimum top width of 6 inches.

Section 101 5 of the ipc tells us not to reduce the pipe size in the direction of flow. Take the roof s total square footage and divide by the total square footage handled by one drain. This reveals that the minimum size for the leader pipe is 5. The use of 4 x 5 downspout outlets starts at a depth of gutter of 4 5 inches.

The availability of 7 inch top width k style gutter has been poor in the past. Can be applied to the table in figure 8 to determine the sizes of the various components of the conventional roof drainage system including roof drains vertical leaders and horizontal drainage piping. 1 inch 25 4 mm 1 gallon per minute 3 785 l m. Table 1106 3 vertical leader sizing for si.

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. Rate of rainfall would. When sizing roof drains the limiting factor for the amount of water each drain will carry away is the size of leader therefore increasing. Sizing a roof water drain.

The result is the number of drains needed. 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. Or 12 drains required. System sizing data rainfall when expressed in g p m.