Below to obtain roof area that can be handled by each leader.
Roof drain coverage area.
It is important to remember that no roof area should ever have less than two roof drains.
Equals 32 6 or 33 drains required.
Area roof will require 100 000 3070 32 5 or 33 roof drains for ideal drainage.
The above result is the number of roof drains required for the building.
And then determine from the chart below how many roof drains you require.
Total roof area 500 by 200 100 000 sq.
Roof drains from zurn include combination primary overflow control flow dual outlet siphonic retrofit and more which cater from educational to commercial needs.
Determine rate of rainfall for this example use 4.
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.
Or 12 drains required.
It affects walkability as well as drainage and roofs in areas of high rain or snowfall tend to have steeper pitches.
Therefore the 100 000 sq.
For a 4 hourly rainfall and 4 leader each drain can handle 4 600 sq.
Roof pitch is a determining factor for cost of the roof as well as the roof area and the type of materials used.
Divide the total roof area by the area that one leader will handle.
Divided by the 4 600 sq.
An additional roof drain should be added for each 10 000 square foot area.
Roof pitch affects the actual area of the roof.
Take the roof s total square footage and divide by the total square footage handled by one drain.
A good rule to follow is to provide two roof drains for a total roof area less than 10 000 square feet.
The drains should be placed at a maximum of 75 feet in each direction away from each other.
The result is the number of drains needed.
50 000 4 400 11 36.
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.
Divide total roof area by area found in step 3 to obtain the number of drains required example.
If the result is a fraction less use the next higher number.
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.
Size and placement of rooftop equipment may necessitate additional roof drains.
