Seasonal

The September Gutter Checklist for St. Louis Homes

By St. Louis Gutter Service · September 11, 2026 · 5 min read

Mid-September in St. Louis is the quiet stretch. The spring hail season is behind you, the July storms are done, the sycamores haven't started dropping, and the ground won't freeze for two months. It's the one window where a gutter problem can be fixed on a dry, mild day instead of under leaves or ice. This is the walk-around to do this week, from the ground, no ladder.

What summer did

June and July storms here arrive with straight-line wind ahead of the rain. Wind gets under a gutter that was already loose and lifts it; hail dents the top lip and loosens the corner seals; and two-inch-an-hour rain in a run that lost its pitch overflows at the corner and soaks the fascia. By September the damage has had a couple of months to show itself. The fall secondary storm season — the metro gets a smaller run of severe weather in October and November — and the first ice in December will find every one of those weak points.

The checklist

Walk the whole house once, slowly, looking up.

1. Hangers and straps. Look for a run that dips in the middle or a gap between the back of the gutter and the fascia. Downspout straps should be every eight feet; a downspout that moves when you push it has lost one.
2. Corners. Dark streaks on the fascia or the brick below a corner mean it's been leaking all summer. Sealant fails at 10–12 years and this is the month to reseal, because polyurethane sealant needs a dry day above 40 degrees to cure and won't get one in January.
3. Fascia. Bubbled paint in a band along the roof edge, or a soft spot when you push it with a broom handle, is rot. It needs to be replaced before winter, because a gutter full of ice on soft wood ends up on the lawn.
4. Flow. Run a hose into the far end of each run for two minutes. Water should reach the downspout and come out the bottom. If it puddles mid-run, the pitch is gone. If it backs up, the downspout is blocked.
5. Extensions. Every downspout should end six feet from the foundation. The mower has knocked half of them off since May.
6. Roof edge. From the ground, see whether the shingles overhang the gutter by about half an inch to an inch. Shingles cut short, or a roof with no drip edge, let water run behind the gutter — common on houses re-roofed after a hail claim.
7. Trees. Note which branches hang over which runs. That's where the October load lands, and where guards would pay off.

Fix now, or wait?

Why the dates matter here

St. Louis has a real leaf season and a real winter, back to back. The sycamores along the creeks and the older streets drop in a two-week rush in mid-October; the pin oaks in Kirkwood, Webster Groves and University City hold on into December. Then the first hard freeze arrives, usually late November, and whatever water is sitting in a badly pitched gutter turns to ice. A corner resealed in September has cured and been rained on twice before any of that. A corner found in December waits until March.

What the walk-around can't tell you

Whether the sealant at a corner is cracked but not yet leaking, whether a spike hanger has backed out an inch, and whether the fascia is soft behind a gutter that looks fine. Those are ladder findings, and they're what a gutter cleaning visit is for — the cleaning is the excuse, the inspection is the value. If you found two or more items on the list, a gutter repair visit in September is a morning; the same items in February are a spring project.

After the storm, not before

If a storm has already come through and a section is hanging: photograph it before anything is touched, get the loose piece secured so it doesn't take the fascia with it in the next wind, and route the water away from the foundation with anything to hand. Hail and wind damage to gutters is usually covered under a Missouri homeowners policy minus the deductible, and the photos are what the adjuster wants. We'll add ours.