Calculate the area of a roof to work out how much guttering is required.
Calculate gutter size uk.
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.
5 inch 2 500 square feet.
Choose gutter outlets according to published flow rate capacities.
Calculate effective maximum roof area b c 2 x length of roof area in m installation.
Multiply the drainage area by the roof pitch factor and rainfall intensity to find out the adjusted square footage.
Picking your gutter size.
Multiply the drainage area by the roof pitch factor and rainfall intensity to find out the adjusted square footage.
For accurate project specific advice on rainwater flow calculations contact our friendly knowledgeable team on 0800 644 44 26.
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.
Total roof area also affects runoff.
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.
5 inch 5 520 square feet.
Gutter ratio l1 l1 l2 where.
Gather some basic weather information to calculate the proper size for gutters and downspouts for a house.
Refer to bsen 12056 part 3.
Depending on building type a safety factor should be allowed for the sizing of internal gutters.
5 inch 5 520 square feet.
Then use the information below to see what size gutter you need.
Roof drainage layout and calculations.
An inch of rain is not much but it if falls in half an hour it could flood a gutter.
For a typical gutter run up to a maximum of 10m the ratio of gutter lengths is calculated from.
Then use the chart below to see what size gutter you need.
5 inch 5 520 square feet.
The total rainfall and how rapidly it falls will affect the runoff from the roof.
6 inch 7 960 square feet.
Match your downspouts to the gutter size you chose in step 7.
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.
6 inch 7 960 square feet.
If a roof s various drainage areas call for different size gutters go for the biggest one k style.
For example a 5 inch gutter system requires at least 2 x 3 downspouts and a 6 inch gutter system requires 3 x 4 downspouts.
These figures are based on a rainfall intensity of 75mm hr roof pitch not exceeding 50º gutters running full.
If a roof s various drainage areas call for different size gutters go for the biggest one k style.
Now finally you can find the appropriate gutter size by looking at the following figures showing the relationship between different gutter systems and the roof area they ll be able to drain.
