Chimney leak repair
Water stains on the ceiling next to the chimney, or water in the fireplace? Here's where chimney leaks come from and how they're fixed.
A chimney passes through the roof, which makes it one of the most common sources of roof leaks. Water can get in at several points, and the stain inside isn't always right below the source. A good chimney contractor tracks down where the water is actually entering before recommending a fix.
Where do chimney leaks come from?
- Flashing. The metal that seals the joint between the chimney and the roof. Failed sealant, lifted step flashing or flashing that was never counter-flashed into the brick are frequent culprits.
- Crown. A cracked crown lets water into the top of the chimney.
- Missing cap. Rain falls straight down the flue.
- Porous brick and mortar. Masonry absorbs water, especially when mortar joints are eroded.
- Condensation. An oversized or unlined flue serving a modern furnace or water heater can produce condensation that looks like a leak.
Signs of a chimney leak
- Ceiling or wall stains near the chimney
- Water or rust in the firebox or on the damper
- Damp or musty smell from the fireplace
- Peeling paint or wallpaper on the chimney breast
- White deposits on brick in the attic or basement
- Stains or rust at the furnace or water heater vent connection
How are chimney leaks fixed?
The fix matches the source: reflashing with step and counter flashing cut into the mortar joints, sealing or replacing the crown, adding a cap, repointing eroded mortar, or applying a breathable masonry water repellent. If condensation is the problem, a properly sized liner usually solves it. Many leaks have more than one source, so a thorough inspection saves money in the long run.
Roofer or chimney contractor?
Flashing sits where the roof and chimney meet, so either trade may handle it. A chimney contractor is the better call when the problem might involve the crown, cap, masonry or liner as well. If you're replacing your roof, it's a good time to have chimney flashing redone and the chimney checked.
What affects the cost?
- The source. A cap costs far less than reflashing or masonry work.
- Roof type and pitch. Slate and steep roofs take more care.
- Interior damage that needs separate repair.
Prices come from the chimney company after they've inspected the chimney. We don't quote prices ourselves, and a phone estimate is only a starting point.
Where we connect you with help
Common questions
Why does my chimney only leak in some storms?
Wind-driven rain from a certain direction often reveals a specific flashing or masonry weak point. Note which storms cause it; that helps the contractor find the source.
Can roofing tar fix chimney flashing?
It can buy time, but it cracks and fails. Proper step and counter flashing is the lasting fix.
Related services
- Chimney masonry repair and tuckpointing
- Chimney relining
- Chimney caps and crowns
- Chimney inspection and sweeping
More background: Northeastern PA chimney guide.
Crumbling bricks or a leak by the fireplace?
Call now and a local chimney company will come inspect it and quote the repair.