Formula To Calculate Gutter Size

The downspout and gutter sizing calculator is located on the tools cad and apps page of the smacna website.

Formula to calculate gutter size.

Total roof area also affects runoff. Enter larger gutter widths in the yellow boxes to find out how wide your gutters need to be given the length that you want to go between downspouts. Minimum top opening width max. 6 inch 7 960 square feet.

Gutter sizing step 4 calculate water handling capacity for gutter downspout options. Then use the chart below to see what size gutter you need. If a roof s various drainage areas call for different size gutters go for the biggest one k style. Roof length x half roof width x roof height 2 roof area.

So for a roof that is 5 m long with a height of 4 m and the. 5 inch 5 520 square feet. Calculate roof area to be drained by your gutter system and note roof pitches. Gutter sizing step 1 determine roof area to be drained.

To limit the effects of thermal expansion in gutters 50 ft. The simple way to calculate gutter sizes. An inch of rain is not much but it if falls in half an hour it could flood a gutter. Multiply the drainage area by the roof pitch factor and rainfall intensity to find out the adjusted square footage.

The total rainfall and how rapidly it falls will affect the runoff from the roof. 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. Gather some basic weather information to calculate the proper size for gutters and downspouts for a house. Downpipe and eaves gutter calculator valley gutters generic rain water outlets for flat roofs.

Downspout sizes must not exceed the bottom width of the gutter. Then use the information below to see what size gutter you need. To calculate the effective roof area you should use this formula. Adding additional downspouts will require less gutter and downspout volume resulting in smaller gutters downspouts.

When selecting and. If a roof s various drainage areas call for different size gutters go for the biggest one k style. Multiply the drainage area by the roof pitch factor and rainfall intensity to find out the adjusted square footage. The capacity of a sloped rectangular gutter may be approximated by using a gutter cross section area not less than that of a semicircular gutter and.

The gutter and downspout size required is highly dependent on the amount of gutter and the spacing of the downspouts. 15 m is a practical maximum gutter length to be served by a downspout. There are two things you need to know. Simplified app for android phones.

Water pipe size calculator information video water pipe size calculators size every pipe in your project in seconds with just 3 clicks. Overflow calculator for eaves gutters. Please lower the maximum spacing between downspouts to see this effect. Commercial roof structures can be complex consisting of many areas shapes and configurations.