A letter from your insurance company asking for a WETT inspection is one of the most common reasons people call us. It usually arrives when you buy a house with a wood stove or fireplace, when you switch insurers, or when you add a wood-burning appliance to a home that did not have one. This post explains what WETT is, why insurers want the report, what the inspection involves, and what happens when something does not pass.
What WETT means
WETT stands for Wood Energy Technology Transfer. WETT Inc. is the Canadian non-profit that trains and certifies the people who install, sweep, and inspect wood-burning systems. A WETT inspection is an inspection performed by a WETT-certified person who documents whether the appliance, chimney, and venting are installed and maintained to the installation code, CSA B365, and the manufacturer's instructions. There is no government WETT licence; the certification is what gives the report its standing with insurers.
Why insurers ask for one
Wood-burning appliances are a leading cause of residential fires, and most of those fires trace back to installation problems: too little clearance to combustibles, inadequate floor protection, a chimney that is undersized, damaged, or never cleaned. Insurers in Ontario have responded by requiring a WETT inspection report before they insure a wood-burning appliance, typically at a new policy or a change of ownership and sometimes at renewal. Without the report, many will exclude the appliance or decline the policy.
What the inspection covers
- The appliance itself: make and model where visible, condition of the firebox, door, gaskets, baffles, and glass.
- Clearances from the appliance and connector pipe to walls, ceilings, mantels, and other combustibles, measured against the manufacturer's listed clearances or the code defaults.
- Floor protection: size and material of the hearth pad or hearth extension.
- The connector (stove pipe): material, joints, screws, support, slope, and length.
- The chimney: type (masonry or factory-built), liner condition, cap and spark arrestor, termination height above the roof, and signs of creosote, water damage, or overheating.
- Combustion air, dampers, and any signs the appliance has been overfired or modified.
The result is a written report, usually with photographs, that states what was inspected, what complies, and what does not. Most inspections take one to two hours. A WETT inspection does not include sweeping the chimney; if the chimney is too dirty to inspect, the report will say so and a sweep comes first.
The most common failures
In older city homes it is usually the chimney: deteriorated clay-tile liners, missing dampers, and chimneys that once vented coal or oil and were never relined for wood. In rural homes it is usually the installation: a stove set too close to a wall, a hearth pad that is too small, single-wall pipe passing through a ceiling, or a connector held together with duct tape and hope. Inserts added to an old fireplace without a full liner connection are a frequent finding everywhere.
What happens if something fails
A deficiency is not the end of the appliance. The report tells you what needs to be corrected and to what standard. Many fixes are straightforward: a larger hearth pad, a heat shield to reduce clearance, a new connector, a chimney cap. Some are bigger, such as relining a masonry chimney. Once the work is done, a re-inspection documents the correction and your insurer gets an updated report.
Booking a WETT inspection
If you are buying, book the WETT inspection with your home inspection so both happen in one visit and the findings land in one report. If you own the home and your insurer has asked, tell us the appliance type and whether there is a specific insurer form, and we will complete it. We are WETT certified and inspect wood stoves, fireplaces, inserts, and outdoor furnaces across Southern Ontario from our base in Puslinch.