How Many Downspouts Do I Need On My Gutter

Once you add up the square footage of your roof you can then determine the number of downspouts.

How many downspouts do i need on my gutter.

You can hire a professional to dig a trench and bury a drain pipe for about 12 to 25 a foot. In areas with heavy rainfall your installer may also determine that for optimal flow you want downspouts on each end of a gutter run even if it s only about 20 feet. Adding a 2 by 3 rectangular downspout for instance boosts your gutter s capacity by 600 square feet of drainage area. Use the chart below to figure out how many extra downspouts you need.

Care must be taken to ensure the gutters are correctly sloped for proper drainage. Expect to pay more if the route is obstructed by tree roots or pavement. As with gutters a downspout s capacity must match or exceed the expected runoff. The typical recommendation is one downspout for every 20 to 30 feet of gutters.

There are many more important factors that can change this broad rule. The rule is that a downspout must be present for every 40 feet of gutter. Roof area the locale s rainfall intensity and gutter capacity determine how many square inches of downspout are needed. How many downspout installations should your gutters have.

For most homes this means installing spouts at either end of a gutter section. 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. A general rule of thumb is one downspout per 20 feet of guttering but more may be necessary depending on the local weather the size of the drainage area and the design of the gutter system. 2 by 3 inches 600 square feet.

First you must consider how many downspouts you will need. 3 by 4 inches 1 200 square feet. If we have to sum it up in a single rule gutters need a downspout around every 30 to 40 feet. As with gutters a downspout s capacity must match or exceed the expected runoff.

If you want a neater look try burying the downspouts. A square inch of downspout can drain 1 200 square feet of roof during a rain with an intensity of one inch per hour. Most gutter installers add a downspout about every 20 or 30 feet of gutter although depending on the slope of your roof and the rooflines you may need more. Rectangular 2 by 3 inches 600 square feet 3 by 4 inches 1 200 square feet.

Doubling the number of downspouts halves the required capacity for each. Adding a 2 by 3 rectangular downspout for instance boosts your gutter s capacity by 600 square feet of drainage area. So if you have a 50 foot long gutter you need two downspouts typically one at each end. But it a job many homeowners can do says mark weisman owner of mark s lawn and landscape in halethorpe maryland.

Poorly designed or installed gutters and downspouts can cause rainwater to pool around the base of the home or back up into the gutters. Size downspouts to fit the gutter. The number of downspouts can be determined by the surface square feet of your roof.