Fraser Valley winters are wet. A compromised chimney lets water in — and that leads to costly repairs. Here's what to look for before the season hits.
The Fraser Valley gets a lot of rain. Chilliwack averages about 1,600mm of precipitation a year, and a significant chunk of that falls between October and March. A chimney that's holding up fine in summer can become a serious water entry point the moment the rains hit — and the damage builds quietly inside the masonry long before you see it on the ceiling.
Getting your chimney checked before fall is the cheapest masonry maintenance decision you can make. Here's what to look for.
1. The Chimney Crown
The chimney crown is the concrete or mortar cap that covers the top of the chimney, surrounding the flue liner. It's designed to direct water away from the flue opening. It's also the first place to fail.
Look from the ground with binoculars if you can. You're looking for cracks across the crown, pieces that are lifting or missing, or significant crumbling at the edges. A cracked crown lets water directly into the top of the chimney stack — that water has nowhere to go but down.
2. The Mortar Joints
The mortar between the bricks holds everything together and, more importantly, keeps water out. On a chimney, which takes direct weather from all sides, the mortar deteriorates faster than on a sheltered wall.
Again, binoculars from the ground. You're looking for mortar that appears recessed, crumbly, or missing in sections. Any joint where you can see daylight between the brick and the mortar is a point where water can enter and freeze.
3. Spalling or Cracked Bricks
Spalling is when the face of a brick breaks off, usually from freeze-thaw cycles. Water gets into a small crack in the brick face, freezes, expands, and pops the face off. Once you see spalled brick on a chimney, it means the brick has absorbed water and that process is underway.
Cracked bricks — full-depth cracks, not just surface marks — are a more serious structural concern and need a closer look from a mason.
4. White Staining (Efflorescence)
Efflorescence is that white, chalky deposit you sometimes see on brick faces. It's not mould — it's mineral salts carried to the surface by water moving through the masonry. It's harmless in itself, but it tells you water is getting through the chimney and moving toward the surface. That's the real problem.
Efflorescence on the inside of your firebox, on the hearth, or on the walls near the chimney base is a clear sign of water infiltration.
5. Flashing Issues
The flashing is the metal (usually lead or galvanized steel) that seals the joint between the chimney and the roof surface. It's a common entry point for water because the chimney and the roof move independently — the chimney on its own foundation, the roof on the framing. That movement cracks the sealant and opens gaps.
Look for rust stains running down the chimney from the roofline, or for gaps where the flashing has pulled away from the brick. Both indicate the flashing seal has failed.
6. Interior Signs
Inside the house, look for water staining on the ceiling or walls near the chimney, a damp smell from the firebox, or rust on the damper assembly. These are late-stage signs — the damage has been building for a while by the time you see them inside.
What to Do If You Find Problems
Minor issues — small crown cracks, a few recessed mortar joints — can often be handled with targeted repairs before winter. More significant damage may require extensive repointing or a chimney rebuild. Either way, addressing it before the wet season hits is far cheaper than dealing with water damage after it gets inside your home.
We do chimney inspections, repairs, and rebuilds across Chilliwack and the Fraser Valley. Give us a call and we'll come take a look.