How to Find a Gutter Leak Before You Call Anyone
A gutter leak is easy to find if you look while the water is running. Ten minutes with a garden hose on a dry day tells you more than a week of watching during storms — and September in Houston gives you plenty of dry mornings between the afternoon storms to do it.
The hose test
Put the hose in the gutter at the end farthest from the downspout and let it run at about half pressure. Walk the run from the ground and watch for drips. Then move the hose to the other side of the house. Note where the water comes out and how — a steady drip at one point, a sheet over the front edge, or water running down the fascia behind the gutter. Those are three different problems.
Do it from the ground with a helper on the hose. You don't need to be on a ladder for this part, and on a two-story home you shouldn't be.
Drip at one point
Almost always a corner, end cap or seam. Look for a dark streak on the fascia or a wet spot on the ground directly under a corner. The sealant has failed. This is the one leak that's a reasonable DIY job on a single-story home: clean the joint with a wire brush and rubbing alcohol, let it dry, and apply a polyurethane gutter sealant (not silicone) inside the joint. Sealant needs the joint dry, which in Houston means picking a morning after two dry days, and it wants a few hours before the next storm. If the metal at the corner is corroded through, it needs a new corner piece — that's a repair call.
Sheet of water over the front edge
Not a leak — an overflow. The gutter is pitched wrong, the downspout is too small, or the run is undersized for the roof. We covered the diagnosis in why gutters overflow in Houston. Sealant won't fix this. A surprising number of people reseal every corner on the house, twice, before somebody tells them the downspout is the problem.
Water running down the fascia behind the gutter
Either the gutter has pulled away from the fascia — you'll see a gap at the top edge — or the roof has no drip edge and water is running back under the shingles. Look up from below with a flashlight. A gap means the hangers have let go; that's a re-hang. No drip edge is a roofing detail, cheap to add, and something we flag on every inspection. If the fascia itself is stained dark and soft, the leak has been going on for years and the board is probably done — see fascia and soffit repair.
Downspout leaks: elbows and outlets
If water drips from a downspout elbow or seam when it's raining, the elbow has separated or a screw hole has opened up. Snap it back together and add a self-tapping screw; if it's split, replace the elbow ($10 part). This is the most common downspout repair Houston-area homes need and the easiest, and it matters more than it looks: a separated elbow dumps the entire run at the slab.
If the drip is at the top instead, where the downspout meets the gutter, the problem is the outlet — the hole cut in the gutter for the downspout — was sealed badly or the sealant has failed. Same fix as a corner: clean and reseal from inside the gutter. On older systems the outlet was cut with tin snips and never sealed at all; you'll see a ragged hole and a drip line straight down the back of the downspout.
Leaks that show up as something else
- A wet spot on the ceiling near an outside wall. Often water running behind the gutter into the soffit, not a roof leak. Check the fascia above it.
- Mud splashed up the brick in one spot. Overflow or a disconnected downspout above it.
- A trench in the mulch under the roofline. Overflow along that whole run, or no gutter there at all.
- Green algae on one section of siding. A slow corner drip that keeps that wall wet.
When to stop and call
- The gutter is sagging or pulling away (hangers, possibly fascia)
- The fascia is soft when you push on it (rot — nothing can be hung on it)
- More than two or three leak points on the house (the system is at end of life — repair or replace walks through that)
- It's a two-story roofline and you're not comfortable on a ladder that tall
A repair inspection from us includes the hose test from the ladder, a check of every corner and the fascia, and a written price. Most single-leak repairs are $150 to $250; the pricing page lists the rest.
Need gutter work in Houston?
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