Rainwater Off Roof Calculator

For example if you have a roof that measures 1 500 square feet that equals 216 000 square inches.

Rainwater off roof calculator.

Water catchment calculator how much rainwater can you harvest. Rainwater collection calculator in gallons rainwater can be collected from the roofs using the rain water harvesting method. Factors such as evaporation wetting and soaking into the ground are not considered here. Once you have the square footage number enter it into the rainwater collection calculator above.

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. To get an idea how much water the roof of your own house might yield use the rainfall harvest calculator above. Use our metric system version. Code to add this calci to your website.

Multiply the area of your roof by the amount of rainfall you wish to calculate for. The catchment areais multiplied by the depth of rain that falls on it to give the total volumeof waterproduced. Just a half inch of rain falling on a 1 000 square foot roof will yield 300 gallons of water. Use the zoom tool in the lower right hand corner of the map to get closer so you can see draw on your roof.

Although this calculation is simple in principle the units can make it a headache. If you don t already have rain gutters on your house this one time investment is the biggest cost you ll face. Need help selecting which tank is right for you. Rain barrel supplies list.

The collectable rainwater from the roof can be calculated in gallons using this calculator based on the rainfall and area. 1 500 x 144 216 000 multiply those 216 000 square inches by the rainfall. This capacity can be calculated using the following formula. Since rainwater is collected from rooftops you will need to work out the total surface area of roof s that will be used to catch rainwater.

Use our water catchment and water usage calculators below to make your selection easier. So a 50 x 20 roof is 600 x 240 multiply the roof dimensions by the number of inches of rainfall. The resulting figure represents the surface area of your roof in square metres. Gutters and a downspout.

To work out the surface area simply multiply the length in metres by width for square or rectangular roofs. Annual rainfall in millimetres x roof surface area in square metres roof catchment capacity. The number of feet multiplied by 144 equals inches. The area measurement will appear right above the map.

Then click on the outer points of your roof and a polygon will instantly be created. Column 1 column 1 column 1 column 1. Take the dimensions of the footprint of your roof and convert them to inches.