Roof Slope Gutter Clearance

Weather bureau records the maximum rainfall that could possibly happen in a 5 minute period in inches per hour for various regions.

Roof slope gutter clearance.

For example if you have 30 feet of guttering the calculation is 1 4 x 3 0 75 i e. You can measure pitch with a 2 foot level and a tape measure. Generally a contractor that drains a gutter onto a lower roof will say that it is an industry standard whereas a contractor that rants against it will say that it s not best building practice. The distance below the projected roof plane varies with pitch.

12 in 12 or higher 1 3 9 in 12 to 11 in 12 1 2 6 in 12 to 8 in 12 1 1 4 in 12 to 5 in 12 1 05 flat to 3 in 12 1. The numbers indicate the rise of the roof over it s run. For a gently sloped 5 in 12 pitch place the front lip of the gutter 3 4 in. If the run is long you may need flashing to cover the exposed part of the facia.

Hold one end of the level against the roof level it and then measure the distance between the roof and the underside of the level at its midpoint which gives you a 12 inch run. The general rule is to slope the gutters at 1 4 th inch per 10 feet of gutters. If the slope is slanted too sharply the gutters can t function at full capacity. Slope the gutter down form there towards the spout.

Required clearance of gutter below extended roof line roof pitch clearance below extended roof line 0 in 12 2 in 12 1 3 in 12 5 in 12 6 in 12 8 in 12 9 in 12 or greater. For a steeper 7 in 12 pitch 1 2 in. It s usually expressed as a number that looks like a fraction such as 1 12 for a very shallow roof or 18 12 for one that s very steep. Below the projected roof plane.

There is no building code citation that forbids a gutter from draining onto a lower roof. And for a 12 in 12 pitch 1 4 in. It depends on who you ask this question. Water will blow in there and rot the timber facia.

The steeper a roof s pitch the more windblown rain it can collect. So it s a matter of what the home inspector or contractor considers acceptable. If the gutter slope isn t properly positioned it will pool in the system and spill over the sides. This means the downspout end of the gutter should be set 3 4 of an inch lower than the other end.

Roof pitch roof pitch factor. Not only do your gutters need sloped at a precise angle but the downspouts need specific direction as well. Roof pitch is very important for right roof gutter sizing. As a general rule gutter slope is set at 1 4 inch per 10 feet of guttering.