How Much Rain Falls On Your Roof A Year

An average suburban roof of 200m 2 with such a rain fall can potentially harvest 100 000l of rainwater 200m 2 500mm 100 000l.

How much rain falls on your roof a year. The number of feet multiplied by 144 equals inches. 1 500 x 144 216 000 multiply those 216 000 square inches by the rainfall. Average rainfall for select cities. If you live in portland or your average rainfall is 37 07 inches and you have a 1500 square foot roof.

So if you have 2 500 square feet of roof available for water catchment and a single inch of rain falls one day we see that. Use square kilometers for large areas. So a 50 x 20 roof is 600 x 240 multiply the roof dimensions by the number of inches of rainfall. Keep in mind most rain falls over 2 3 months of a year.

Take the dimensions of the footprint of your roof and convert them to inches. To get an idea how much water the roof of your own house might yield use the rainfall harvest calculator above. This calculation assumes a 90 efficiency. When you look at the numbers it s surprising how much water you can collect every time it rains.

If your average rainfall was 25 inches year your annual collection potential is 1 120 x. It isn t uncommon for an area to collect up to 350mm of rain in just one month even in rural areas. Use meters for areas such as your roof or yard. To calculate the runoff from any given rainfall.

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. I think you ll be surprised about much rain really does fall during a rainstorm. Use our metric system version. For example if you have a roof that measures 1 500 square feet that equals 216 000 square inches.

To find how much rain you can collect in an average rain year multiply this number by the average inches of rain. Select one or more methods to choose the size of your area. Multiply the area of your roof by the amount of rainfall you wish to calculate for. Rain barrel supplies list.

1500 x 0 6 x 37 1 33 390 gallons a year. Just a half inch of rain falling on a 1 000 square foot roof will yield 300 gallons of water. It is the middle of july in georgia and both you and your tomatoes are wilting in your yard both looking to the sky and hoping for rain. You can enter numbers into any or all of the boxes below.