Gutters, leaks and keeping water out of your house

How water gets into a house

Water rarely shows up where it enters. A stain on a bedroom ceiling is only the spot where water finally reached drywall. The opening can be several feet uphill, because water runs along rafters, decking, nails and pipes before it drops.

It helps to think of three routes:

• Through the roof covering. Cracked, lifted or missing shingles, exposed nail heads, and a roof that has simply worn out.
• Around anything that interrupts the roof. Chimneys, skylights, plumbing vents, valleys and the places where a roof meets a wall. These joints are sealed with flashing, and they are the usual weak points.
• Off the roof and down the house. Gutters that overflow, downspouts that empty at the foundation, and roof edges that stay wet and slowly soak the fascia, soffit and siding behind them.

Southwest Ohio gives all three routes plenty of work. Rain falls in every season, spring storms can drive water sideways, and winters swing back and forth across freezing, so water gets into small gaps and then expands as it freezes. Much of the region also sits on clay-heavy soil that drains slowly, which means water dumped beside a foundation tends to linger there instead of soaking away.

Flashing is where many leaks start

Flashing is thin metal, usually steel, aluminum or copper, worked under shingles and siding to steer water over a joint instead of into it. You find it around chimneys, skylights, vent pipes, dormers, valleys, and along walls that rise above a roof.

Shingles last a long time compared with the sealants and small fasteners at those joints. When you see a leak around a chimney or a wall, the flashing or the sealant on it is a more likely suspect than the shingles around it. Common problems include:

• Old caulk or roofing cement that has dried, cracked and pulled away.
• Metal that has rusted through, lifted, or been bent by ice or a fallen branch.
• Rubber boots around plumbing vents that have cracked in the sun. These are small parts and a very common source of drips.
• Flashing that was never lapped correctly in the first place, where each piece should overlap the one below it like shingles do.

Smearing sealant over a leak is a temporary patch at best, and it can trap water and hide the real problem. Proper repair usually means lifting the surrounding shingles, replacing or re-lapping the metal, and putting everything back in the right order. That work happens on a sloped, often slick roof, so it is a job for a roofer. Our guide to finding the source of a roof leak covers what you can safely check from inside the house.

Gutters and downspouts

A roof sheds a lot of water in a short time. Gutters collect it at the edge and downspouts carry it away from the house. When they work, water never touches the fascia, walls or foundation. When they do not, it goes to all three.

The usual failures are simple. Leaves, shingle grit and seeds pack the trough so water spills over the front. Gutters pull away from the fascia as fasteners loosen or the board behind them softens. Seams leak. A low spot holds standing water that rusts or freezes. A downspout clogs, or it empties right at the foundation.

Where the water lands matters as much as where it is collected. Downspouts should discharge well away from the house, using extensions or splash blocks, and the ground near the foundation should slope away from the walls. With slow-draining clay soil, water released at the corner of a house can find its way into a basement or crawl space wall.

Some older homes in the region have built-in or box-style gutters set into the roof edge. These can fail in ways that are hard to see, because a leak at the gutter shows up inside the wall or ceiling. If your house has them, have a roofer look at them regularly. For everything about cleaning and upkeep, see our guide to gutter maintenance through the seasons, and if gutters need to be replaced or re-hung, that is covered under gutter services.

Ice dams and winter water

An ice dam is a ridge of ice at the roof edge that traps melting snow behind it. The trapped water backs up under the shingles and into the house. The cause is almost never the gutters. It is heat from the living space escaping into the attic, warming the roof deck, and melting snow on the upper roof. That meltwater runs down to the cold overhang, where it refreezes.

Ohio winters, which hover around freezing for stretches, are well suited to this cycle: a snowfall, a few days of sun or milder air, then a hard freeze. Houses with thin attic insulation, gaps around attic hatches and light fixtures, or poor ventilation are the ones most likely to form dams.

The lasting fix is inside the attic:

• Seal air leaks where warm air gets in, such as around the attic hatch, recessed lights, and pipe and wire openings.
• Bring insulation up to a sound, even depth.
• Make sure the attic can vent, with intake at the soffits and exhaust near the ridge.

In the moment, do not climb onto an icy roof, and do not chip at the ice with a hammer, axe or shovel. You will damage the shingles and risk a bad fall. A roof rake used from the ground can clear snow from the lowest few feet, with care around power lines. If water is already coming through a ceiling, a roofer can advise on safe steps to relieve the dam. Ice and gutter damage after a hard winter can also be a storm damage matter, so document it with photos.

Fascia and soffit rot

The fascia is the board along the roof edge that your gutters hang from. The soffit is the underside of the overhang. Together they close off the rafter ends and let the attic breathe. They are also among the first parts to rot when water is mismanaged.

Watch for peeling paint, dark or streaked boards, soft spots you can dent with a screwdriver tip, gutters that sag or pull away, and daylight or small animals where the soffit meets the wall. Wood that stays damp year after year decays, and soft fascia cannot hold gutter fasteners, so the problem grows.

Repair means finding why the board stayed wet. Overflowing gutters, a missing drip edge at the roof edge, or a leak from above are common causes. Replacing rotten boards without fixing the cause only starts the clock again. Rot that has reached the rafter ends or roof deck is a structural concern and should be assessed by a roofer before anything is covered up with new trim.

A maintenance calendar

You do not need a long list. A few checks at the right times catch most problems.

Early spring

• From the ground, look for shingles that are lifted, cracked or missing after winter.
• Check gutters for sagging, pulled-away sections and ice damage.
• In the attic, look at the underside of the roof deck for dark stains or damp insulation.

Late spring, after storms

• Look for debris on the roof, bent flashing and flooded gutters.
• Walk around the house during a heavy rain, if you can do so safely, and watch where water goes.

Early fall

• Clean gutters and flush downspouts once the leaves in your yard start to drop, and again after most have come down.
• Check downspout extensions and the soil slope at the foundation.
• Inspect plumbing vent boots and sealant around chimneys and skylights, from the ground with binoculars.

After the first hard freeze and again in midwinter

• Look for icicles in unusual places or a heavy ridge of ice along the eaves. Both point to attic heat loss.
• Check ceilings and the tops of exterior walls for new stains.

Staying off the roof is the safe default. Binoculars, a camera with a zoom lens, and a look from inside the attic tell you a lot. If something looks wrong, a roof repair visit costs far less than rebuilding a ceiling and insulation after a long leak.

When to call a roofer

Call a roofer for any problem that sits on the roof, around a chimney or skylight, or along rotted fascia. Also call after a storm that leaves lifted shingles, or if you see water stains that grow. Work on a pitched roof, on a wet or icy surface, or near power lines should not be a do-it-yourself project. Gutter cleaning from a ladder is the most common way homeowners get hurt, so use a stable ladder on firm ground, keep three points of contact, and hire it out if you are not comfortable.

If you cannot tell whether a stain is old or active, a roofer can check it with a moisture meter and trace it back. For questions about the process, see our frequently asked questions, or contact us to talk through what you are seeing.

Frequently asked questions

7 min read.