For a 4 hourly rainfall and 4 leader each drain can handle 4 600 sq.
Roof drain coverage area.
Or 12 drains required.
Roof drains from zurn include combination primary overflow control flow dual outlet siphonic retrofit and more which cater from educational to commercial needs.
The result is the number of drains needed.
Roof pitch is a determining factor for cost of the roof as well as the roof area and the type of materials used.
When placing roof drains it is good design practice to locate the drains no more than 50 feet from the roof perimeter nor more than 100feet apart.
Size and placement of rooftop equipment may necessitate additional roof drains.
Roof pitch affects the actual area of the roof.
A good rule to follow is to provide two roof drains for a total roof area less than 10 000 square feet.
It is important to remember that no roof area should ever have less than two roof drains.
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.
Smith carefully designs and manufactures a full line of roof drains deck drains scupper drains promenade and parking area drains and more to satisfy both the artistic eye of the architect and the calculating mind of the engineer.
If the result is a fraction less use the next higher number.
50 000 4 400 11 36.
Therefore the 100 000 sq.
An additional roof drain should be added for each 10 000 square foot area.
It affects walkability as well as drainage and roofs in areas of high rain or snowfall tend to have steeper pitches.
Divided by the 4 600 sq.
Divide the total roof area by the area that one leader will handle.
Equals 32 6 or 33 drains required.
Area roof will require 100 000 3070 32 5 or 33 roof drains for ideal drainage.
Below to obtain roof area that can be handled by each leader.
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.
The above result is the number of roof drains required for the building.
Take the roof s total square footage and divide by the total square footage handled by one drain.
Each 4 drain size in a 6 hourly rainfall area will accommodate drainage of 3 070 sq.
Sizing schedule wa o r i d m t n v c a u t a z c o w y n m t x.
And then determine from the chart below how many roof drains you require.
The drains should be placed at a maximum of 75 feet in each direction away from each other.
