Gallons Of Water Per Square Foot Of Roof

If your average rainfall was 25 inches year your annual collection potential is 1 120 x 25 28 000 gallons year.

Gallons of water per square foot of roof.

Multiply the cubic feet by the amount of water per cubic foot which is 7 48 gallons. The answer is about 623 gallons. It doesn t take many sticks leaves or needles to impede the proper flow of. For example on a 2 000 square foot roof you can collect 2 000 x 0 56 1 120 gallons inch of rain.

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. Calculate rainwater collection in gallons rain fall inches. Just multiple the square footage of roof space you have available x 0 6 gallons per square foot per inch of rain and you can see how much water you can collect from each inch of rain that falls. The collectable rainwater from the roof can be calculated in gallons using this calculator based on the rainfall and area.

So a 50 x 20 roof is 600 x 240 multiply the roof dimensions by the number of inches of rainfall. Take a guess what is the volume of water that runs off a 1 000 square foot roof during a 1 rain storm. Take the dimensions of the footprint of your roof and convert them to inches. To figure out the square footage of a surface multiply the width x length.

The square footage of a roof is the same whether it is pitched or flat. Or 0312 gallons per minute sq. Up to 6 12 7 12 8 12. Meaning you can capture about 62 gallons per sq ft.

Using a 10 000 sq. Roof area the 3 inch rainfall will produce 18 700 gallons in one hour at the rate of 312 gallons per minute. To calculate the runoff from any given rainfall. In this example you would multiply 7 48 times 600 to get 4 488 gallons of water.