Pitch Rate For Gutters

Gutter should be pitched 1 16 or greater per foot for proper drainage.

Pitch rate for gutters.

Gutter can be run level for appearance but addition downspout will be necessary see section on proper gutter and downspout sizing. Multiply the number of feet by 1 16 inch to determine the total slope the gutter requires. Many of today s newer homes have more complex roof lines. This means the downspout end of the gutter should be set 3 4 of an inch lower than the other end.

The steeper a roof s pitch the more windblown rain it can collect. Steeper pitches require less clearance. These rates correspond to 0 133 in min 3 4 mm min and 0 08 in min 2 mm min. It takes 96 15 square feet 8 93 square meters of surface with 1 inch per hour 25 mm hr of water to correspond with 1 gpm 0 063 l s flow rate.

You can measure pitch with a 2 foot level and a tape measure. To get started measure the side of the house directly under the gutter to determine its length in feet. Gutters need to be pitched at a 5 degree angle. For example if the gutter is 16 feet long the end near the down spout must be 1 inch lower than the starting end.

A steeper pitch will make water run down faster and require an oversized gutter. In my opinion some pitch is good i d say 1 8 per ft. This allows the water to flow gently but. Roof pitch is very important for right roof gutter sizing.

I have never had an issue with this as for mud and sludge build up it makes no difference it dont move inside the gutter. Local codes may require that drainage systems only be designed for the latter. Increase the pitch of the gutter. Gutters should be placed below the extended roof line so that snow and ice can slide clear.

As a general rule gutter slope is set at 1 4 inch per 10 feet of guttering. My gutter installer keeps them close to level unless something above dumps into it. Increasing the pitch increases a gutter s handling capacity but the gutter may look askew over a long run. For example if you have 30 feet of guttering the calculation is 1 4 x 3 0 75 i e.

The standard is about inch per 10 feet.