Roof Sqaure Footage Per Area Drain And Dwonspout

If a roof s various drainage areas call for different size gutters go for the biggest one k style.

Roof sqaure footage per area drain and dwonspout.

A square inch of downspout can drain 1 200 square feet of roof during a rain with an intensity of one inch per hour. Maximum horizontal projected roof area that can be drained in square feet. Two hundred feet of gutter can cost anywhere between 660 and 4 500. 6 inch 7 960 square feet.

After you have calculated the square footage use following calculations. If we have to sum it up in a single rule gutters need a downspout around every 30 to 40 feet. We have rounded smith s data and comment further below. How many downspout installations should your gutters have.

There are 5 easy steps to figure out how many drains your commercial roofing project will need. 5 inch 2 500 square feet. 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. Calculate the total roof area by multiplying its length by width.

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. A house in chicago has a roof whose actual drainage area is 1 000 square feet. Calculate total roof area. Roof drainage capacity for other roof drain pipe or leader diameters.

Adapted from smith 2014 cited below. Doubling the number of downspouts halves the required capacity for each. 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. 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.

Gutters come in a wide range of materials the cost depends on which you choose. Roof area the locale s rainfall intensity and gutter capacity determine how many square inches of downspout are needed. Vinyl gutters cost 2 to 5 per linear foot. 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.

To do that simply multiply drainage area calculated earlier by roof pitch factor and rainfall intensity. 5 inch 5 520 square feet. 6 inch 3 840 square feet.