How Much Gutter Do I Need? Sections, Hangers and Downspouts

Most homes use 5 inch K-style gutters in 10 ft sections. 60 ft of gutter in two runs takes 6 sections, 4 connectors and 32 hangers at 24 inches, and the gutter must slope 1.5 inches along its length. The gutter calculator gives the parts for your house.

Parts for a run of gutter

For one run, with hangers every 24 inches (and every 18 inches for snow):

Downspout parts, by height

For one downspout, in 10 ft sections, with elbows and straps:

A whole house

A house with four runs of gutter (120 ft in all), four outside corners and five downspouts, each 20 ft high, takes 12 sections, 8 connectors, 64 hangers, 8 end caps, 4 corners, 10 downspout sections, 15 elbows and 20 straps.

Slope and downspouts

• Slope. About 1/4 inch for every 10 ft toward the downspout. A gutter with the downspout in the middle falls both ways from the high point at each end.
• Downspouts. One for every 20 to 30 ft of gutter, and one at each low point. Put them at corners where you can, and run the water away from the foundation.
• Hangers. About every 24 inches, closer in snow country, and one near every joint and corner.
• Joints. Seal every joint with gutter sealant, and join the sections so that the water runs over the joint, not into it.

Installing and caring for them

• Check the fascia board first: gutters need a solid board to hang from, and a rotten one needs replacing.
• Set the high end first, then snap a chalk line to the low end for the slope.
• Use parts from one system, since the profiles are not all the same.
• Clean the gutters in the spring and the fall, or fit guards, and check the downspouts for blockages.
• For a second or third story, use a safe ladder with a stabilizer or hire a pro: a fall from a ladder is a common serious injury.

A gutter also feeds a rain barrel: see the rainwater collection calculator, and the roofing calculator if the roof needs work too. Estimates only: check the parts with the supplier.

Frequently asked questions