Roof Water Runoff Calculator

So a 50 x 20 roof is 600 x 240 multiply the roof dimensions by the number of inches of rainfall.

Roof water runoff calculator.

Rain barrels store and reuse rainwater helping to reduce the overtaxing of sewer systems and protect the quality of groundwater. How to calculate roof runoff. For a rectangular house this is simply done by multiplying the length by the width of the roof. To calculate the runoff from any given rainfall.

Then click on the outer points of your roof and a polygon will instantly be created. Simplified suitable for flattish roofs with little or no vertical faces or steep roofs draining to one side of box gutter only or any roof if you are in a hurry and make the necessary allowances for all catchments. Submit your design let nds evaluate and help you with preparation of your submittal drawings and specs. If your roof plan is more complicated break it up into smaller more easily calculable areas and then add those areas together for the total area.

The catchment areais multiplied by the depth of rain that falls on it to give the total volumeof waterproduced. Calculate the total area of your roof. For a large roof it is recommended to have drains placed at multiple locations within the area of the roof. A simple rain catchment system can provide water for outdoor use resulting in.

Increasing the angle of a flat roof will always increase the speed of water movement across the surface. Take the dimensions of the footprint of your roof and convert them to inches. The area measurement will appear right above the map. Although this calculation is simple in principle the units can make it a headache.

National stormwater calculator help prevent pollution by controlling stormwater runoff. Once you have the square footage number enter it into the rainwater collection calculator above. The new nds app is the perfect tool for determining runoff and system requirements on the go. Calculate your drainage install on site.

It s one of the greatest threats to clean water in america today. Box gutter with rain water head at end of box gutter. The calculator has two primary functions. Use the zoom tool in the lower right hand corner of the map to get closer so you can see draw on your roof.

The drainage system of any roof can be located at the edge or in the middle of the roof. The first is that it will size a rain garden for you that treats 1 of rainfall. Factors such as evaporation wetting and soaking into the ground are not considered here.