Gutters and Downspouts: Where Your Fall Rain Actually Goes

Every inch of rain on a roof sends a lot of water to the gutters. Where that water ends up decides whether your basement stays dry, your foundation stays sound and your landscaping survives. Fall, when the leaves come down and the rain picks up, is the best time to check.

01Go out in the rain

The single best inspection you can do is to walk around the house during a steady rain with an umbrella. Look for:

• Water pouring over the edge of the gutter instead of into it.
• Leaks at seams and corners.
• Downspouts that aren't flowing, which usually means a clog.
• Water pooling near the foundation.
• Splash marks or erosion in the mulch under the gutter.

If water is shooting over the gutter at the bottom of a steep roof valley, see preventing gutter overshoot.

02Check the gutters

On a dry day, from a safe ladder (or with binoculars from the ground):

• Clogs: leaves, seeds, shingle granules and nests. Clean them out in late fall after most leaves drop, and again in spring.
• Slope: gutters should slope gently toward the downspouts. A common rule of thumb is about a quarter to a half inch of drop for every 10 feet of gutter. Standing water in a gutter after rain means the slope is off.
• Sagging: loose hangers let gutters pull away from the house.
• Rust, holes and separated seams.
• Fascia damage behind the gutter, a sign water has been getting behind it.

03Check the downspouts

• Clear and flowing. Run a hose down from the top if you're not sure.
• Securely attached to the wall.
• Extended away from the house. Water should come out several feet from the foundation (many pros suggest 4 to 6 feet or more), not right at the base of the wall.
• Pointed downhill, not toward a neighbor's house, a driveway that freezes, or a walkway.
• Underground drains should be clear. If water backs up out of the top of an underground pipe, it's clogged.

04Check the ground

Water that leaves the downspout has to keep moving away. The soil around your foundation should slope away from the house; building codes often call for about 6 inches of drop in the first 10 feet. Low spots, settled soil and mulch piled against the siding all send water back toward the basement.

05Quick fixes

• Clean the gutters and flush the downspouts.
• Add downspout extensions or splash blocks.
• Re-hang sagging gutters with new hangers.
• Seal leaking seams with gutter sealant.
• Regrade low spots next to the foundation with soil, not mulch.
• Consider gutter guards if you have lots of trees, but keep checking; guards still need cleaning.

06Before winter

Clogged gutters freeze solid in winter, and they help cause ice dams. See ice dams: how to spot the risk. Make sure everything flows before the first hard freeze, and keep downspout outlets clear of snow.

07Safety first

Ladder work causes a lot of injuries every year. Use a sturdy ladder on firm, level ground, keep three points of contact, and don't reach out past the ladder rails. For two-story houses or steep roofs, a gutter cleaning service is worth it.

Water you keep away from the house is water you'll never have to pump out of the basement. Add this to your fall home inspection checklist.

Photo: 002 2011 08 15 Regenwasserableitung by Friedrich Haag, CC BY-SA 4.0.

Related: Inspect Your Roof From the Ground: What Binoculars and the Attic Tell You