If the length of the gutter is 10 5 metres 35 feet the amount of slope required is 1 25 cm 1 4 inch multiplied by 1 metres 3 5 feet which when rounded up is 2 5 cm 1 inch.
Slope of roof guttering.
Calculate the gutter slope by dividing the length of the gutter needed by 10.
The minimal slope needed for proper gutter drainage is 1 25 cm 1 4 inch for every 3 metres 10 feet of gutter.
If there s standing water it s not pitched properly.
For spans longer than 40 feet it s wise to have a downspout on each end and start the high spot of the gutter in the center.
125 mm 5 gutter 100 mm 4 downspout.
For example if you have 30 feet of guttering the calculation is 1 4 x 3 0 75 i e.
150 mm 6 gutter 100 mm 4 downspout.
2 grade 2 cm per 100 cm run 0 250 inch per 1 ft run.
1 grade 1 cm per 100 cm run 0 125 inch per 1 ft run.
Gutters need to be pitched toward the downspouts for the water to flow properly.
This means the downspout end of the gutter should be set 3 4 of an inch lower than the other end.
Most contractors tend to set the slop at one quarter inch per ten feet of guttering.
As a general rule gutter slope is set at 1 4 inch per 10 feet of guttering.
You want at least a quarter inch of slope for every 10 feet.
To correct this yourself you ll need to measure from the peak to the downspout.
So if you have a 25 foot section of guttering you should set the downspout end of the gutter 5 8 of an inch lower 1 4 x 2 5 5 8 than the other end.
So what s the ideal amount of slope for your gutters.
Get on a ladder after a rainstorm and look in the gutter.
The standard slope for rain gutters is half of an inch for every 10 feet.
Working out gutter slope.