How Much Rain Falls On Your Roof A Year

When you look at the numbers it s surprising how much water you can collect every time it rains.

How much rain falls on your roof a year.

Multiply the area of your roof by the amount of rainfall you wish to calculate for. You can enter numbers into any or all of the boxes below. 1500 x 0 6 x 37 1 33 390 gallons a year. If you live in portland or your average rainfall is 37 07 inches and you have a 1500 square foot roof.

Use square kilometers for large areas. 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. The number of feet multiplied by 144 equals inches. In this example 600 x 240 x 1 144 000 cubic inches of water.

Take the dimensions of the footprint of your roof and convert them to inches. To calculate the runoff from any given rainfall. 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. 1 500 x 144 216 000 multiply those 216 000 square inches by the rainfall.

Select one or more methods to choose the size of your area. Use meters for areas such as your roof or yard. Just a half inch of rain falling on a 1 000 square foot roof will yield 300 gallons of water. Rain barrel supplies list.

To find how much rain you can collect in an average rain year multiply this number by the average inches of rain. I think you ll be surprised about much rain really does fall during a rainstorm. This calculation assumes a 90 efficiency. 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.

Keep in mind most rain falls over 2 3 months of a year. 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. It isn t uncommon for an area to collect up to 350mm of rain in just one month even in rural areas.

For example if you have a roof that measures 1 500 square feet that equals 216 000 square inches. 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. Rainfall calculator english units how much water falls during a storm.