Roof Drains Per Square Foot

The next step is to consult table 1106 3 figure 2 to learn the required size of pipe.

Roof drains per square foot.

They come in a variety of shapes tubes chains etc but their goal is to prevent gutters from overflowing and give water somewhere to go. The speed at which the rain collects at the drain. The roof drain calculator below is based on the maximum amount of rainfall in inches per hour of the hypothetical worst storm in the past 100 years and which has a two percent chance of occurring in any given year. The downspout is the portion of the gutter that drains water away to a safe place on the ground.

For 1 one inch hr. Divided by the 4 600 sq. Hy tech is an authorized distributor of all roof drain manufacturers so you can find what you need when you need it. Equals 32 6 or 33 drains required.

Take the roof s total square footage and divide by the total square footage handled by one drain. Gallons per minute r rainfall intensity inches hour a roof area square feet 0104 conversion factor g p m sq. 0104 x r x a g p m. Area roof will require 100 000 3070 32 5 or 33 roof drains for ideal drainage.

Therefore the 100 000 sq. Measuring the square feet of the roof along with knowledge of local rainstorms is invaluable when. 0 gallons 0 cubic feet. 50 000 4 400 11 36.

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. And then determine from the chart below how many roof drains you require. Using a 10 000 sq. If you need help finding a drain ask our drain wizard or call to speak with our roof drain expert.

The drains should be equally spaced and located symmetrically about the roof. 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. This reveals that the minimum size for the leader pipe is 5. Or 12 drains required.

Each drain can handle 4 600 sq. Round spee d catch basins. Sizing data for conventional drainage. For example a 3 inch per hour rainfall will build up to a 3 inch depth on a flat roof in one hour at the rate of 1 87 gallons per hour sq.

The result is the number of drains needed. Or 0312 gallons per minute sq. 0 cubic feet per second cfs peak runoff volume. Drainage pipe required minimum diameter.

Divide total roof area by area found in step 3 to obtain the number of drains required example. Roof area the 3 inch rainfall will produce 18 700 gallons in one hour at the rate of 312 gallons per minute. 0 submit your design let nds evaluate and help you with preparation of your submittal drawings and specs. Each 4 drain size in a 6 hourly rainfall area will accommodate drainage of 3 070 sq.