How Much Rain Collected From Roof
For example on a 2 000 square foot roof you can collect 2 000 x 0 56 1 120 gallons inch of rain.
How much rain collected from roof. Rain barrel supplies list. If your average rainfall was 25 inches year your annual collection potential is 1 120 x 25 28 000 gallons year. So how can you do the math for your own roof. Just a half inch of rain falling on a 1 000 square foot roof will yield 300 gallons of water.
Rainwater collection calculation formulas and equations roof area ft2 x precipitation amount in x 0 623 amount collected gallons easy formula to remember. Gallons collected per inch of rainfall 0 62 total collecting area of roof in square feet so if you have a 1 000 square foot house you can potentially collect 0 62 1 000 620 gallons of water every time it rains an inch. An average suburban roof of 200m 2 with such a rain fall can potentially harvest 100 000l of rainwater 200m 2 500mm 100 000l. To get an idea how much water the roof of your own house might yield use the rainfall harvest calculator above.
1 of rain on 1 000 sf roof will yield 623 gallons roof area m2 x precipitation amount mm amount collected liters. To find how much rain you can collect in an average rain year multiply this number by the average inches of rain. Keep in mind most rain falls over 2 3 months of a year. When you look at the numbers it s surprising how much water you can collect every time it rains.
With two inches of rain you can collect around 1 240 gallons.