Calculate How Many Downspouts Gutters Need

Cost of vinyl gutters and downspouts.

Calculate how many downspouts gutters need.

One 3x4 downspout will drain 1200 sq. As with gutters a downspout s capacity must match or exceed the expected runoff. Prices range from 6 12 per linear foot for both gutters and downspouts. Heavy rainstorms put a lot more pressure on gutters.

Keeping gutters in good condition is more important than many people realize. Elbows miters end caps gutter outlets gutter wedges gutter offsets coil sheet goods gutter hangers downspout brackets gutter flashings gutter fasteners conductor leader heads aluminum soffit trim gutter decorations downspout guards accessories paint sealant solder polish tile. Gutters come in many sizes. Adding a 2 by 3 rectangular downspout for instance boosts your gutter s capacity by 600 square feet of drainage area.

Particularly wet climates could require better drainage systems than relatively dry climates rainy. Use the chart below to figure out how many extra downspouts you need. 2 by 3 inches 600 square feet. Large gutters can hold more water and may not need as many spouts.

Now architects engineers designers and contractors can easily and accurately size downspouts and gutters according to the specifications in smacna s architectural sheet metal manual 7th edition 2012. In terms of material options most seamless gutters roughly 80 of all installs are made from aluminum. Aluminum is the most popular choice for gutter material because it s lightweight and durable. Roof area the locale s rainfall intensity and gutter capacity determine how many square inches of downspout are needed.

Size downspouts to fit the gutter. Rectangular 2 by 3 inches 600 square feet 3 by 4 inches 1 200. Smaller gutters may need extra downspouts to make up for their low volume. So if you need to install 150 ln ft.

Typically professionally installed aluminum seamless gutters cost 10 12 per linear foot. Cost of aluminum gutters and downspouts. Not only can runoff from a roof ruin landscaping next to a building it may cause erosion that will damage the foundation. From time to time rain gutters wear out and must be replaced.

Of gutters and downspouts you will be spending about 1 500 1 800. 3 by 4 inches 1 200 square. Use the chart below to figure out how many extra downspouts you need. The downspout and gutter sizing calculator is located on the tools cad and apps page of the smacna website.

3200 square feet of roof is calculated as 3200 600 5 33 rounding up you would need 6 2x3 downspouts or 3200 square feet of roof is calculated as 3200 1200 2 67 rounding up you would need 3 3x4 downspouts one 2x3 downspout will drain 600 sq. A square inch of downspout can drain 1 200 square feet of roof during a rain with an intensity of one inch per hour. Adding a 2 by 3 rectangular downspout for instance boosts your gutter s capacity by 600 square feet of drainage area.