How Many Square Feet Of Roof Per Downspout

As an example if your overhang is 12 inches you ll add 2 feet to the overall length and 2 feet to the overall width of the house.

How many square feet of roof per downspout. Measuring the square feet of the roof along with knowledge of local rainstorms is invaluable when making. To do that simply multiply drainage area calculated earlier by roof pitch factor and rainfall intensity. For the vast majority of rains gutter and downspouts. Use the chart below to figure out how many extra downspouts you need.

After you have calculated the square footage use following calculations. Roof area the locale s rainfall intensity and gutter capacity determine how many square inches of downspout are needed. If we have to sum it up in a single rule gutters need a downspout around every 30 to 40 feet. For most homes this means installing spouts at either end of a gutter section.

How many downspout installations should your gutters have. Doubling the number of downspouts halves the required capacity for each. Roof area square feet per linear ft of gutter underneath. 4 inches 1 255 square feet.

This nominal square footage amount is then multiplied by a factor associated with the roof s pitch. 3 inches 706 square feet. Adding a 2 by 3 rectangular downspout for instance boosts your gutter s capacity by 600 square feet of drainage area. Roof pitches in degrees.

Up to 6 12 7 12 8 12. Gutter and downspout water capacity. Most of all is location and your average rainfall during a large downpour. 2 by 3 inches 600 square feet.

Many factors can effect the proper size of gutter. For a 5 inch k style gutter the square footage should be up to 5 500 sq ft and for a 6 inch k style gutter the square footage should be upto 7 900 sq ft.