Common leak spots
Where is the stain? Pick one to narrow it down, then tap a spot to see why it leaks.
Pipe bootsUsually a repair
What you see insideA stain on the ceiling under a bathroom or kitchen, often a small round spot.
Why it leaksThe rubber collar around each plumbing pipe dries out and cracks in the sun, years before the shingles wear out.
See how it should be builtChimney flashingUsually a repair
What you see insideWater stains on the ceiling or wall next to the chimney, or damp brick in the attic.
Why it leaksCaulk or tar around the chimney cracks after a few winters, or the old metal flashing pulls away from the brick.
See how it should be builtWhere a roof meets a wallUsually a repair
What you see insideStains on a wall below a second story, or rot behind the siding.
Why it leaksStep flashing that was reused or never tucked behind the siding lets water run down inside the wall.
See how it should be builtSeam nailsUsually a repair
What you see insideA drip or stain in an odd spot, with nothing wrong you can see on the roof above it. It often shows up only in heavy or wind-driven rain.
Why it leaksWater runs down through the seam where two shingles butt together. If a nail was driven too close to that seam in the row below, the water finds the nail and follows it straight into the wood. The nail is hidden under the shingle above, and the water can travel before it drips, which makes this one of the hardest leaks to find.
Missing kick-out flashingUsually a repair
What you see insideA stain or soft spot on the wall where a lower roof edge meets a wall.
Why it leaksWithout a kick-out, water runs off the roof edge straight into the wall instead of the gutter.
See how it should be builtSkylightsRepair or replace, depends on the roof
What you see insideDrips or stains around the skylight shaft, or fogged glass.
Why it leaksMost skylight leaks come from the flashing around it. Old skylights are often replaced with the roof.
See how it should be builtValleysRepair or replace, depends on the roof
What you see insideA stain below where two roof slopes meet.
Why it leaksValleys carry the most water. Worn shingles or nails too close to the center leak there first.
See how it should be builtRoof ventsUsually a repair
What you see insideStains under a box vent or bathroom vent, often after wind-driven rain.
Why it leaksCracked plastic vents, rusted metal, or vents that were never flashed under the shingles above.
See how it should be builtIce dams at the eavesRepair or replace, depends on the roof
What you see insideStains along an outside wall or where the ceiling meets it, mostly in winter or early spring.
Why it leaksSnow melts, refreezes at the cold edge, and the ice backs water up under the shingles. Usually an attic airflow problem too.
See how it should be builtNail popsUsually a repair
What you see insideSmall drips or brown spots in the middle of a ceiling.
Why it leaksNails work loose and push up through the shingle above, leaving a hole.
Missing or lifted shinglesRepair or replace, depends on the roof
What you see insideA new stain after a windstorm.
Why it leaksWind lifts shingles that didn’t seal or were nailed too high. Many at once usually means the roof is near the end.
Gutters and drip edgeUsually a repair
What you see insideStains on the soffit or the top of an outside wall.
Why it leaksClogged gutters overflow back under the roof edge, or water runs behind a gutter with no drip edge.
See how it should be builtAttic condensation (not a leak)Not a roofing repair
What you see insideSpots all over the ceiling or frost on the nails in winter, but no rain needed.
Why it leaksWarm, wet air from the house condenses on the cold roof deck. It’s an airflow fix, not a roof repair.
See how it should be builtThese are the most common causes. A roofer should find the actual source before fixing anything.
Skip ahead: get a roofer to find it