Calculating Gutter Sizes Uk

Roof length x half roof width x roof height 2 roof area calculate the area of a roof to work out how much guttering is required 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.

Calculating gutter sizes uk.

Where an angle occurs in a length of gutter served by two outlets the reduction factor of 0 85 should only be applied to. 5 inch 5 520 square feet. An inch of rain is not much but it if falls in half an hour it could flood a gutter. 2000 contains maps showing rainfall intensity in litres second per m2 for 1 5 50 and 500 year storms of 2 minute duration.

All external gutters designed for 1 year. Multiply the drainage area by the roof pitch factor and rainfall intensity to find out the adjusted square footage. Calculating effective roof areas where gutter angles are installed effect of angles if a length of eaves gutter includes an angle the flow in the gutter will be impeded and its capacity reduced by 15. Then use the chart below to see what size gutter you need.

Roof drainage layout and calculation amd 17041 2000. 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. Use the formula a l x w where a is area l is length and w is width. The total rainfall and how rapidly it falls will affect the runoff from the roof.

Rainline gutters are available in two shapes and five sizes. Downpipes are available in four. Multiply the drainage area by the roof pitch factor and rainfall intensity to find out the adjusted square footage. As a consequence sizing the gutter spout is key to properly sizing a gutter system.

British standard bs en 12056 3. 5m x 4m x 4 2 40 square metres. Total roof area also affects runoff. If a roof s various drainage areas call for different size gutters go for the biggest one k style.

Design area effective area 5 x 10 x 1 29 64 5m run off 64 5m x 0 022 l s per m 1 42 l s from chart 125 x 100 gutter with 76 ø downpipe appears suitable but check. All gutter systems in the uk should be designed to bs en 12056 3 2000 gravity drainage systems inside buildings. 6 inch 7 960 square feet. Lg 10 133 therefore reduction factor 0 86 d 0 1 gutter capacity x reduction factor 2 84 x 0 86 2 44 l s therefore the proposed system is suitable.

100mm 125mm 150mm 190mm and rectangular 136mm. 15 m is a practical maximum gutter length to be served by a downspout. If a roof s various drainage areas call for different size gutters go for the biggest one k style. Downspout sizes must not exceed the bottom width of the gutter.

Determine the surface area of your roof. This guide provides a basic method for calculating flow requirements or flow capacity. Geographical location and rainfall intensity maps. Gather some basic weather information to calculate the proper size for gutters and downspouts for a house.

Then use the information below to see what size gutter you need.