How Many Downspouts Are Needed For Gutters

The next factor to take into account is the pitch of your roof because the pitch will cause water to flow in a certain direction.

How many downspouts are needed for gutters. Adding a 2 by 3 rectangular downspout for instance boosts your gutter s capacity by 600 square feet of drainage area. Rectangular 2 by 3 inches 600 square feet 3 by 4 inches 1 200 square feet. Use the chart below to figure out how many extra downspouts you need. A square inch of downspout can drain 1 200 square feet of roof during a rain with an intensity of one inch per hour.

The typical recommendation is one downspout for every 20 to 30 feet of gutters. For most homes this means installing spouts at either end of a gutter section. Size downspouts to fit the gutter. There are many more important factors that can change this broad rule.

3 by 4 inches 1 200 square feet. How many downspout installations should your gutters have. First you must consider how many downspouts you will need. As with gutters a downspout s capacity must match or exceed the expected runoff.

Roof area the locale s rainfall intensity and gutter capacity determine how many square inches of downspout are needed. 2 by 3 inches 600 square feet. If we have to sum it up in a single rule gutters need a downspout around every 30 to 40 feet. Poorly designed or installed gutters and downspouts can cause rainwater to pool around the base of the home or back up into the gutters.

The gutter troughs and downspouts must be installed with this pitch in mind so that water flows down instead of remaining stagnant in the gutter trough. Use the chart below to figure out how many extra downspouts you need. As with gutters a downspout s capacity must match or exceed the expected runoff.