Calculate Size Of Gutters

How to calculate gutter and downspout capacity step 1.

Calculate size of gutters.

Then use the chart below to see what size gutter you need. Multiply the drainage area by the roof pitch factor and rainfall intensity to find out the adjusted. Calculations are based on level gutter capacity as experimentally determined by the national institute of standards and technology nist. How do you calculate gutter size.

Run the tape measure from 1 corner of the gutter as far as you can go toward. Rainfall intensity is measured in a 5 minute interval translated. 15 m is a practical maximum gutter length to be served by a downspout. See photos below most residential gutters will measure approximately 5 inches across the top with the actual opening being approximately 4 5 inches.

Measure your gutter across the top from the back where the gutter meets the home to the outer edge. If a roof s various drainage areas call for different size gutters go for the biggest one k style. The steeper a roof s pitch the more windblown rain it can collect. Measure the length of each gutter run.

To limit the effects of thermal expansion in gutters 50 ft. Measuring existing gutters 1. 5 inch 5 520 square feet. Find the width of the gutters.

Measure the roof to get the watershed area the area from which water will run off. Place a sturdy 20 ft 6 1 m ladder on 1 side of your house so that you can reach. Multiply length peak to. Adjusting for pitch and rainfall.

Measure the height of. Find the rainfall intensity for your locale. 5 inch standard k style gutter shop 5 gutterbrush.