How Much Rain Collected From Roof

If you have 1 000 square feet of roof on your house and it rains just 1 inch you can collect 600 gallons of water to be used in your garden for washing your car or just for drop irrigation around your property.

How much rain collected from roof.

That s 600 less gallons you have to pay for and use from your town water supply. An average suburban roof of 200m 2 with such a rain fall can potentially harvest 100 000l of rainwater 200m 2 500mm 100 000l. Just a half inch of rain falling on a 1 000 square foot roof will yield 300 gallons of water. 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. It isn t uncommon for an area to collect up to 350mm of rain in just one month even in rural areas. To find how much rain you can collect in an average rain year multiply this number by the average inches of rain. For example on a 2 000 square foot roof you can collect 2 000 x 0 56 1 120 gallons inch of rain.

Rainwater collection calculation formulas and equations roof area ft2 x precipitation amount in x 0 623 amount collected gallons easy formula to remember. To get an idea how much water the roof of your own house might yield use the rainfall harvest calculator above. So how can you do the math for your own roof. 1 of rain on 1 000 sf roof will yield 623 gallons roof area m2 x precipitation amount mm amount collected liters.

Rain barrel supplies list.