The masonry chimney, the concrete crown that sheds water off the top, the metal cap that keeps rain and animals out of the flue, and the flue liner inside that safely carries combustion gases — from a wood-burning appliance, furnace, or water heater — out of the house.
Two different risks. Moisture: a missing cap or cracked crown lets water into the masonry, where Canadian freeze-thaw cycles expand it and crumble the mortar (spalling) — a slow, escalating, and avoidable repair. Safety: a damaged, undersized, or missing flue liner is a carbon-monoxide and fire risk. Chimneys are easy to miss because they're up high and rarely photographed in listings — squarely in Casaroo's wheelhouse to flag. For wood-burning systems specifically, the recognised Canadian benchmark is a WETT (Wood Energy Technology Transfer) inspection against CSA B365, the standard for installing and maintaining solid-fuel-burning appliances; many insurers ask for a WETT inspection on homes with a wood stove or fireplace.
How to spot it
From the ground or roofline: a missing or rusted cap; a cracked crown; crumbling or missing mortar and spalling brick; a leaning chimney; and water stains on interior walls or ceilings near the chimney chase. Inside a fireplace: a damaged firebox, a rusted or stuck damper, or a strong damp/soot smell.
What it costs
Cap ~$150–500; crown repair or repointing ~$1,000–4,000; relining ~$2,500–7,000+, depending on height and access.
What to do
Address soon. Have a chimney specialist — WETT-certified for any wood-burning system — inspect and sweep before first use, and budget cap/crown work. Confirm coverage if there's a wood-burning appliance.
Education and triage, not a home inspection. Casaroo flags chimney issues from your exterior and firebox photos — a WETT-certified chimney professional confirms the flue and crown.
Common questions
What is Chimney, flue & cap?
The masonry chimney, the concrete crown that sheds water off the top, the metal cap that keeps rain and animals out of the flue, and the flue liner inside that safely carries combustion gases — from a wood-burning appliance, furnace, or water heater — out of the house.
Why does it matter for home buyers?
Two different risks. Moisture: a missing cap or cracked crown lets water into the masonry, where Canadian freeze-thaw cycles expand it and crumble the mortar (spalling) — a slow, escalating, and avoidable repair. Safety: a damaged, undersized, or missing flue liner is a carbon-monoxide and fire risk. Chimneys are easy to miss because they're up high and rarely photographed in listings — squarely in Casaroo's wheelhouse to flag. For wood-burning systems specifically, the recognised Canadian benchmark is a WETT (Wood Energy Technology Transfer) inspection against CSA B365, the standard for installing and maintaining solid-fuel-burning appliances; many insurers ask for a WETT inspection on homes with a wood stove or fireplace.
How can I spot it?
From the ground or roofline: a missing or rusted cap; a cracked crown; crumbling or missing mortar and spalling brick; a leaning chimney; and water stains on interior walls or ceilings near the chimney chase. Inside a fireplace: a damaged firebox, a rusted or stuck damper, or a strong damp/soot smell.
How much does it cost to fix?
Cap ~$150–500; crown repair or repointing ~$1,000–4,000; relining ~$2,500–7,000+, depending on height and access.
WETT inspections evaluate solid-fuel systems against the CSA B365 standard. A WETT-certified professional confirms; Casaroo flags, it does not inspect.
Last reviewed 2026-06-27.
Casaroo reviews each guide against current pricing, code, and insurer practice. Cost ranges are 2026
estimates that vary by region, size, and access — confirm specifics with a licensed professional.