Buying The House
A chimney is one of the most expensive items on a house and one of the least examined during a purchase.
Short answer
Get a chimney inspection during the conditional period, separate from the general home inspection. For a wood appliance get a WETT inspection, because your insurer will want one anyway and the findings can be substantial. The items that cost money are the liner, the crown, the masonry above the roof and the flashing.
Why the general inspection is not enough
Most home inspectors look at the firebox and the visible exterior and do not camera the flue.
The expensive findings are inside: cracked or missing tiles, an unlined flue, a deteriorated smoke chamber.
The crown and the masonry above the roof are frequently assessed from the ground or from a photograph.
Clearances and the hearth on a wood stove are a WETT matter and most home inspectors are not certified.
A gas insert needs a gas technician, which is a separate trade again.
And the orphaned water heater question after a furnace upgrade is a specific thing to look for and is routinely missed.
Get the WETT report conditionally
If there is a wood stove, an insert or a wood-burning fireplace, get the WETT inspection during the conditional period. Your insurer will want one, the findings can run into real money — relining, clearances, hearth work — and it is far better to know before closing than after.
What to ask about
Is the flue lined, and what is the condition of the liner — with a camera rather than an opinion.
Is the crown a crown or a mortar wash, and is there a cap.
What is the condition of the masonry above the roof line, which is where the rebuild money is.
Is the flashing at the roof line correct — step flashing, counter flashing in a joint, a cricket behind a wide stack.
What appliances vent into it, including the water heater.
And when it was last swept and inspected, with the records if they exist.
Using the findings
A liner, a crown, a partial rebuild and flashing are each real numbers, and together they can be substantial — which makes them a negotiation with evidence behind it.
Clearances and hearth findings on a wood stove have to be resolved for insurance, which gives them a deadline.
An uncertified or site-built appliance may simply not be insurable, which is worth knowing before closing.
Keep the report, because it is the baseline and it is what the insurer wants.
Budget from it rather than being surprised by it.
And if the vendor has had work done, ask for the invoices and the WETT report, because a documented chimney is worth more than an undocumented one.
Common questions
Is a home inspection enough for the chimney?
Rarely. The expensive findings are inside the flue and need a camera.
Do I need a WETT inspection?
For any wood appliance, yes — your insurer will want one.
What is routinely missed?
The orphaned water heater on an oversized flue after a furnace upgrade.