August 1, 2021
Repair

6 Roof Repair Tips: Find and Fix a Leaky Roof

6 Roof Repair Tips: Find and Fix a Leaky Roof

You can stop leaks yourself

No experience required. We show you how to locate and repair the most common types of roof leaks. Most leaks take only a few minutes to repair.

Leaky Roof Overview

Leaky Roof Overview

If you have water stains spreading through ceilings or running down walls, the cause is probably a leaky roof. Locating the leak is the hard part; Fixing roof leaks is usually pretty easy. We’ll show you a few simple tricks for finding and repairing most of the common types of leaky roofs. But if you live in the snow belt and in winter you leak only on warm or sunny days, you probably have ice dams. We will not go into roof leak repair in this story.

If you have a leaky roof, you’d better get it fixed right away, even if it doesn’t bother you too much or if you’re buying a new roof next year. Even in a short time, small leaks can lead to big problems, like mold, rotten frames and siding, destroyed insulation, and damaged ceilings. The intermittent leak that caused a costly repair bill was obvious from stains on the ceiling for over two years. If the owner had fixed it right away, the damage and subsequent repairs would have been minimal.

How to Find Roof Leaks

How to Find Roof Leaks

When trying to locate a leak, start by looking at the roof uphill from the stains. The first thing to look for is any penetration into the roof. Items that penetrate the roof are by far the most common source of leaks. In fact, it is rare for leaks to develop in open areas of unbroken tiles, even older roofs. Penetrations can include roof pipes and vents, chimneys, dormers, or anything else that projects through the roof. They can be several feet above the leak or to the right or left of it.

If you have access to the attic, the easiest way to locate a leak is to go up there with a flashlight and search for the evidence. There will be water spots, black marks, or mold. But if access is a problem or you have a vaulted ceiling, you will have to go up to the roof and examine the suspects.

A Trick for Finding Difficult Leaks

A Trick for Finding Difficult Leaks

If a leak is difficult to find, hire a helper and get up to the roof with a garden hose. Start small, soaking the area just above where the leak appears in the house. Isolate the areas when running the hose. For example, soak the downhill side of a fireplace first, then each side, then the top on both sides. Have your helper stay inside the house waiting for the drip to appear. Let the hose run for several minutes in one area before moving it a bit more towards the ceiling. Have your helper shout when a drip is seen. You’ll be in the neighborhood of the leak. This process can take more than an hour, so be patient and don’t move the hose too soon. Buy your helper dinner. If running water doesn’t reveal the exact location of the leak, don’t be shy. Begin removing the tiles in the suspicious area. With them removed, there will be evidence of the leak and you can trace it directly to the source. You’ll see faded felt paper or water-stained or even rotten wood directly under and around a leaky ceiling.

Solution for a Small Leak

Solution for a Small Leak

Some roof leaks are difficult to locate. Sometimes the water appears at a point on the ceiling distant from the leak. If your ceiling has a plastic vapor barrier between the drywall and the attic insulation, push the insulation aside and look for flow spots on the plastic. Often times, the water runs into the openings in the vapor barrier, as in ceiling lamps.

If you can’t see any telltale flow marks, and since the stain is quite small, look at the bottom of the ceiling for “brighteners.” A gloss is a nail that missed the framing member, in this case when the carpenter nailed the roof sheathing to the joists. Moisture that escapes into the cold attic from rooms below often condenses on cold nails. You can sometimes detect this if you go up to your attic on a cold night. Nails will look white because they are frosted. When the attic gets a bit hot during the day, the frost melts and drips, then the nails refreeze at night and so on. The solution is to simply cut the nail with a side cutter.

How to Fix Roof Vents

How to Fix Roof Vents

Some roof leaks are difficult to locate. Sometimes the water appears at a point on the ceiling distant from the leak. If your ceiling has a plastic vapor barrier between the drywall and the attic insulation, push the insulation aside and look for flow spots on the plastic. Often times, the water runs into the openings in the vapor barrier, as in ceiling lamps.

If you can’t see any telltale flow marks, and since the stain is quite small, look at the bottom of the ceiling for “brighteners.” A gloss is a nail that missed the framing member, in this case when the carpenter nailed the roof sheathing to the joists. Moisture that escapes into the cold attic from rooms below often condenses on cold nails. You can sometimes detect this if you go up to your attic on a cold night. Nails will look white because they are frosted. When the attic gets a bit hot during the day, the frost melts and drips, then the nails refreeze at night and so on. The solution is to simply cut the nail with a side cutter.

Fix Walls and Dormers

Fix Walls and Dormers

Water does not always enter the surface of the tiles. Wind-driven rain often comes from above the roof, especially around windows, between corner boards and siding, and through cracks and knots in siding. Dormer walls provide many places where water can drip onto the roof. Caulk can be old, cracked, or even missing between corner boards and between window edges and siding. Water gets into these cracks and makes its way behind the flashing and into the house. Even sealant that appears intact may not seal against adjoining surfaces. Dig with a putty knife to see if the area is sealed. Remove any suspicious caulk and replace it with a high-quality caulk. Also check the siding on the flashing step. Replace any cracked, rotten, or missing siding, making sure the new piece overlaps the step flashing by at least 2 inches. If you still have a leak, pull the corner boards and check the overlapping flashing at the corner. There is often old, hardened putty where the two pieces overlap at the inside corner.