Calculate Size Of Gutters

Total roof area also affects runoff.

Calculate size of gutters.

If a roof s various drainage areas call for different size gutters go for the biggest one k style. Gather some basic weather information to calculate the proper size for gutters and downspouts for a house. Overflow calculator for eaves gutters. So for a roof that is 5 m long with a height of 4 m and the roof width is 8 m which makes the half roof width 4m we can calculate the effective roof area like this.

Adding additional downspouts will require less gutter and downspout volume resulting in smaller gutters downspouts. Water pipe size calculator information video water pipe size calculators size every pipe in your project in seconds with just 3 clicks. Then use the information below to see what size gutter you need. The downspout and gutter sizing calculator is located on the tools cad and apps page of the smacna website.

An inch of rain is not much but it if falls in half an hour it could flood a gutter. Downspout sizes must not exceed the bottom width of the gutter. 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. 15 m is a practical maximum gutter length to be served by a downspout.

5 inch 5 520 square feet. 5 inch 5 520 square feet. 6 inch 7 960 square feet. Downspouts also come in different sizes such as 2 3 inches and 3 4 inches in size.

The total rainfall and how rapidly it falls will affect the runoff from the roof. If a roof s various drainage areas call for different size gutters go for the biggest one k style. Simplified app for android phones. Downpipe and eaves gutter calculator valley gutters generic rain water outlets for flat roofs.

To choose the right size gutters for a building that doesn t already have them you can quickly calculate the drainage area of the roof and adjust for pitch and rainfall to find the adjusted square footage. Multiply the drainage area by the roof pitch factor and rainfall intensity to find out the adjusted square footage. Then use the chart below to see what size gutter you need. You only need a ladder chalk tape measure level paper and pen.

Calculate the area of a roof to work out how much guttering is required. Calculations are based on level gutter capacity as experimentally determined by the national institute of standards and technology nist. The gutter and downspout size required is highly dependent on the amount of gutter and the spacing of the downspouts. When you are completing a gutter replacement the first point to note is that gutters come in different sizes.

They can be 4 5 or 6 inches.