Calculate Gutter Size Uk

Add a fall to the gutters which we recommend you do anyway.

Calculate gutter size uk.

Frequency and positioning of outlets downpipes. Calculate the number of outlets per. If a roof s various drainage areas call for different size gutters go for the biggest one k style. Change the style of gutters to one with a greater capacity.

2000 contains maps showing. To limit the effects of thermal expansion in gutters 50 ft. Gutter ratio l1 l1 l2 where. For a typical gutter run up to a maximum of 10m the ratio of gutter lengths is calculated from.

Increasing the capacity of your gutter system. If you ve got a simple gable end roof then it s easy you only need to know two figures one for either slope. That will show how much water a gutter will have to drain. British standard bs en 12056 3.

15 m is a practical maximum gutter length to be served by a downspout. 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. Geographical location and rainfall intensity maps. Move the outlet downpipe from the end of the gutter to the middle.

Choosing the right size of gutters and downpipes step 1. The most logical way to choose your gutter size would be according to the area of your roof. Downspout sizes must not exceed the bottom width of the gutter. Determine the rainfall intensity for your location.

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. L1 l2 selecting gutter size there is no standard rate of rainfall in the uk so for accurate calculations refer to an approved weather authority to get a site specific rainfall level. Calculate the square footage by getting up there with a tape measure.

Using the 5280 square feet example from step 6 you will choose a gutter size that can handle at least 5280 square feet. Divide the inch per hour watershed of the roof by the 5 minute rainfall intensity. 5 inch 5 520 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.

That is how much rain a roof can drain during the most intense rainfall.