In this example 600 x 240 x 1 144 000 cubic inches of water.
How many gallons of rain on my roof.
The answer is about 623 gallons.
Although this calculation is simple in principle the units can make it a headache.
Take the dimensions of the footprint of your roof and convert them to inches.
In the form below choose an area s and a rainfall amount to see how many gallons of water fell from the sky onto that area.
Either way you would like to know how much rain has fallen how many gallons have come down from the skies onto your roof yard block or town.
To find how much rain you can collect in an average rain year multiply this number by the average inches of rain.
3 to account for losses and inefficiency you can expect to collect about 75 of the actual rainfall so your calculation should be multiplied by 75.
To calculate the runoff from any given rainfall.
You might even want to know how many baths you could get from your rainstorm.
For example on a 2 000 square foot roof you can collect 2 000 x 0 56 1 120 gallons inch of rain.
So a 50 x 20 roof is 600 x 240 multiply the roof dimensions by the number of inches of rainfall.
However calctool s unit menus remove this issue doing all the unit conversion for you.
So for each inch of rainfall your roof could collect 1 246 gallons of rainwater.
If your average rainfall was 25 inches year your annual collection potential is 1 120 x 25 28 000 gallons year.
The collectable rainwater from the roof can be calculated in gallons using this calculator based on the rainfall and area.
So multiply 623 gallons by the number of surface square feet of your roof.
An inch of rainfall on a square foot of surface area yields 623 gallons.
Either way you would like to know how much rain has fallen how many gallons have come down from the skies onto your roof yard block or town.
Rainwater can be collected from the roofs using the rain water harvesting method.
In our example it would be 623 x 2 000 which equals 1 246.
Rainwater collection calculator in gallons.
You might even want to know how many baths you could get from your rainstorm.
You have to admit that whether you re in a drought situation or not it s hard to pass up that much of a free thing.
The amount of rain that fell during your storm is dispayed below.