Roof Sqaure Footage Per Area Drain And Dwonspout

Roof area the locale s rainfall intensity and gutter capacity determine how many square inches of downspout are needed.

Roof sqaure footage per area drain and dwonspout.

6 inch 3 840 square feet. 5 inch 5 520 square feet. If we have to sum it up in a single rule gutters need a downspout around every 30 to 40 feet. To do that simply multiply drainage area calculated earlier by roof pitch factor and rainfall intensity.

Two hundred feet of gutter can cost anywhere between 660 and 4 500. Metal gutters vary in price from 6 to 12 for aluminum and 9 to 20 for steel to 25 or more for high end copper. To size the vertical roof drain for the same parameters 5 000 square feet of room area and 6 per hour of rain consult table 1106 2 figure 3. Doubling the number of downspouts halves the required capacity for each.

A house in chicago has a roof whose actual drainage area is 1 000 square feet. 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. According to the chart for 1 8 slope per 12 of pipe for 5 000 square feet of roof area with a 6 per hour of rainfall the required pipe size is 8. Determine leader or pipe size.

If a roof s various drainage areas call for different size gutters go for the biggest one k style. We have rounded smith s data and comment further below. Maximum horizontal projected roof area that can be drained in square feet. Adapted from smith 2014 cited below.

Plumbing codes typically use the vertically projected roof area for drainage design and they often use a square foot allowance per square inch of downspout for 1 in hr 25 mm hr rainfall that varies with diameter for example 3 in 76 mm. 6 inch 7 960 square feet. 5 inch 2 500 square feet. Calculate total roof area.

For most homes this means installing spouts at either end of a gutter section. After you have calculated the square footage use following calculations. Max area of roof draining to one down. Roof drainage capacity for other roof drain pipe or leader diameters.

Vinyl gutters cost 2 to 5 per linear foot. Calculate the total roof area by multiplying its length by width. A square inch of downspout can drain 1 200 square feet of roof during a rain with an intensity of one inch per hour.