Water is the number one enemy of a masonry chimney. It gets in through the crown, through porous brick, through failed flashing where the chimney meets the roof, and straight down an uncapped flue. Once inside, it rusts the damper, rots the framing, stains the ceiling and, when it freezes, breaks the brick apart.
Bison diagnoses chimney leaks from the roof and the attic, fixes the actual source, and then waterproofs the masonry with a vapor-permeable water repellent so the chimney can dry out instead of soaking up the next storm. Most Overland Park chimney leaks have more than one cause, so we check all of them.
What's included in our chimney waterproofing & leak repair
- Leak diagnosis from the roof, attic and interior, with photos
- Step and counter flashing repair or replacement
- Crown crack sealing or crown rebuild
- Cap installation on open flues
- Application of breathable siloxane masonry water repellent (10-year manufacturer warranty)
- Mortar joint repair where water was getting in
Where chimney leaks actually come from
The crown: cracks in the top slab let water run down between the flue tiles and the brick. The flashing: the metal that seals the chimney to the roof pulls away, rusts or was never counter-flashed properly. The brick itself: masonry is porous, and a chimney with no water repellent absorbs gallons of water in a heavy rain. The flue: an uncapped flue is an open pipe into your house.
We rarely see just one of these. A typical Johnson County leak repair fixes the flashing, seals the crown, caps the flue and treats the brick in a single visit.
Why we use breathable water repellent, not sealer
Paint-on sealers trap moisture inside the brick, which then freezes and spalls the face off. The siloxane-based repellents we apply soak into the masonry, repel liquid water and still let water vapor escape. They are invisible when dry and last about ten years before a reapplication.
Signs your chimney is leaking
- Brown stains on the ceiling or wall near the fireplace
- Dripping or a musty smell in the firebox after rain
- White efflorescence or dark damp patches on the chimney brick
- Rust on the damper or firebox
- Peeling paint or bubbling drywall near the chimney
Noticing any of these? Call (913) 555-0100 and we will get you scheduled.
Chimney Waterproofing & Leak Repair: frequently asked questions
Why does my chimney leak only in heavy rain?
Light rain is absorbed by the brick and evaporates. Heavy, wind-driven rain overwhelms the masonry and finds the cracks. That pattern usually points to porous brick and a cracked crown rather than flashing.
How long does chimney waterproofing last?
The water repellent we use carries a 10-year manufacturer warranty. Flashing and crown repairs last as long as the roof and chimney do.
Is a chimney leak covered by insurance?
Storm damage often is; gradual deterioration usually is not. We document everything with photos so you can file if it applies.
Where we offer chimney waterproofing & leak repair
Based in Overland Park, serving all of Johnson County and the Kansas City metro with no trip fees.
