Gutter Problems That Come From the Roof, Not the Gutter
A fair number of the "gutter leaks" we're called to in St. Louis aren't gutter leaks. The gutter is fine; the roof above it is putting water in the wrong place. This matters because a gutter crew can reseal a corner all day and it won't help, and because the fix is often a roofer's job, not ours. Here's how to tell.
The drip edge
A drip edge is an L-shaped strip of metal that sits under the first course of shingles at the eave and hangs over the back of the gutter. Its job is to carry water from the shingle edge into the gutter instead of letting it wick back under the shingle and run down the fascia. Missouri's residential code, like most, requires it on new roofs, and it's been standard practice for decades. It's also the first thing skipped by a crew doing a fast roof replacement.
St. Louis has a particular version of this problem. The metro gets hail most springs, and a lot of roofs in the county have been replaced on insurance claims, sometimes twice in fifteen years. Claim work is done to a scope sheet, quickly, and if the original roof had no drip edge the new one often doesn't either. So there are thousands of 1960s–90s houses in Florissant, Affton, Ballwin and O'Fallon with a five-year-old roof and no drip edge, and the fascia behind the gutter has been wet ever since.
How to spot it: from the ground, look at the eave. You should see a strip of metal, usually white or brown, just under the shingle edge and behind the gutter. If you see shingle, then a gap, then gutter, there's no drip edge. Fascia that's stained or peeling in a continuous band along the roof edge, rather than just below the corners, is the other tell.
The fix: a roofer slips drip edge under the first course, or a gutter crew adds a gutter apron — a wider flashing that does the same job from the gutter side — when re-hanging. Either is a few hundred dollars for a whole side.
Shingle overhang
Shingles should extend past the drip edge by about a quarter to three-quarters of an inch, so water drops cleanly into the gutter. Cut them flush with the fascia and water clings to the underside and runs back. Cut them two inches long and they droop, break, and in a wind-driven storm water blows past the outside of the gutter altogether.
How to spot it: flush shingles show as a clean, straight roof edge with the gutter well below it. Long shingles curl down over the gutter's front lip. Both show up as wet fascia or water on the ground right below the eave during a moderate rain, with the gutter not particularly full.
Valleys
A roof valley — where two roof planes meet in a V — concentrates water. On a two-story hip-roofed home in Chesterfield or Wildwood, a single valley can deliver water from 400 square feet of roof to one spot on the gutter at a rate the gutter can't absorb, and it shoots over the front lip or, in wind, past the gutter entirely. It looks like an overflow. The gutter is clean and pitched right.
How to spot it: water pouring over the gutter at one specific point directly below a valley, in the first minutes of a storm, while the rest of the run is fine.
The fix: a splash guard — a small bent piece of aluminum screwed to the front lip below the valley — for $40–$80, or a 6-inch gutter on that run if the roof area is big enough. Sometimes a diverter on the roof above to spread the flow.
Roof problems that show up as gutter symptoms
| What you see | Looks like | Actually is |
|---|---|---|
| Wet fascia in a long band, gutter not full | Gutter leaking along the back | Missing drip edge |
| Water on the ground under the eave in light rain | Gutter overflow | Shingles cut flush |
| Overflow at one spot under a V in the roof | Clogged gutter | Valley surge |
| Water behind the gutter only at one end | Failed end cap | Step flashing at a wall or chimney failed above |
| Granules and grit filling the gutter | Debris | Shingles shedding; the roof is aging |
| Ice forming behind the gutter | Gutter pitch | Ice dam from attic heat loss |
The last row is the winter version. Ice that forms behind the gutter, against the fascia, is meltwater from a warm roof deck refreezing at the cold eave — an attic problem, covered in ice, snow and gutters in St. Louis.
What we do about it
Every gutter repair or replacement estimate includes a look at the roof edge from the ladder, because there's no point hanging a new gutter behind an eave that's sending water down the fascia. If it's a drip edge, we'll say so and either add a gutter apron as part of the job or tell you to have a roofer look at it before we come back. If it's a valley, the splash guard or the 6-inch run goes on the estimate.
What we won't do is reseal a corner three times because the water keeps coming. If the gutter's been "fixed" twice and the fascia is still wet, look up.
Need gutter work in St. Louis?
Call for a free estimate. Mon–Sat 7am–7pm.