An annual chimney inspection is the most reliable method of identifying hazards in a wood-burning system before they result in a fire or carbon monoxide incident. In Canada, the standard framework for this work is administered by WETT Inc. (Wood Energy Technology Transfer), which certifies technicians and defines inspection scopes across three levels.
WETT Inspection Levels Explained
WETT Inc. defines three levels of inspection, each covering a progressively wider scope of the installation. Knowing which level applies to your situation helps set expectations before scheduling a technician.
Level 1 — Basic Visual Inspection
This is the standard annual check for a chimney that has been operating normally and has not undergone changes. The inspector visually examines accessible portions of the appliance, connector (stovepipe), and chimney without the use of specialized tools or cameras. It covers:
- Condition of the firebox, including door gaskets and glass if applicable
- Stovepipe connections and clearances to combustibles
- Accessible portions of the flue interior
- Chimney cap, crown, and visible exterior masonry or cladding
- Evidence of water entry, blockage, or animal intrusion
Level 2 — Extended Inspection
A Level 2 inspection is required in specific circumstances: when a property changes hands, when any component of the system has been altered or replaced, or following an event such as a chimney fire, lightning strike, or seismic activity. It includes everything in Level 1, plus:
- Video or camera inspection of the full flue interior
- Inspection of accessible attic, crawl space, and basement areas adjacent to the chimney
- Assessment of clearances within concealed spaces
Real estate transactions in Canada involving homes with solid-fuel appliances commonly require a Level 2 WETT inspection as a condition of sale. Some insurance providers also request documentation of a Level 2 inspection before underwriting a policy on a home with a wood stove.
Level 3 — Invasive Inspection
Level 3 is reserved for situations where Levels 1 and 2 indicate a serious hazard that cannot be fully assessed without opening up building components. This may involve removing sections of wall, ceiling, or chimney cladding. It is uncommon in routine maintenance and is typically triggered by a documented chimney fire or severe structural concern.
Insurance companies operating in Canada vary in their requirements for solid-fuel heating systems. Some ask for a WETT Level 1 or Level 2 inspection report at policy renewal or at the time of purchase. Contact your insurer directly to confirm current documentation requirements for your province and policy type.
What an Inspector Looks For
Regardless of inspection level, technicians assess several recurring categories of concern:
| Category | Examples of Findings |
|---|---|
| Clearances | Stovepipe too close to combustibles; inadequate floor protection |
| Flue condition | Cracked clay tile liners; deteriorating mortar joints; excessive creosote |
| Connector system | Improper gauge stovepipe; missing or loose support brackets; incompatible materials |
| Chimney cap and crown | Missing cap; cracked crown wash; open joints allowing water entry |
| Appliance condition | Deteriorated door gasket; cracked firebox; non-functional damper |
Preparing for an Inspection
A few practical steps make an inspection more efficient and reduce the likelihood of rescheduling:
- Allow the stove and flue to cool completely — at minimum 24 hours after the last fire
- Clear the area immediately in front of and around the stove for access
- Have available any documentation from the original installation, including the stove certification label and any permits if the unit was installed while permits were required
- Know whether a chimney fire has occurred since the last inspection
- Note any observations from recent use — unusual smoke odour in the house, visible smoke in the room, difficulty establishing draft
After the Inspection: Understanding the Report
A WETT inspection report documents observed conditions and typically classifies findings as deficiencies requiring immediate correction, items to monitor, or advisory notes. Deficiencies that present an immediate fire or CO hazard should be addressed before operating the appliance again.
Common repairs following an inspection include: re-lining the flue with a flexible stainless steel liner, replacing damaged clay tile sections, repointing mortar joints in masonry chimneys, installing or replacing a chimney cap, or correcting stovepipe clearances. Most of these tasks require a qualified trades professional, and some may require a building permit depending on the scope of work and province.
A searchable list of WETT-certified technicians, organized by province and postal code, is available at wettinc.ca. Certification levels and the scope of work each technician is authorized to perform are listed in the directory.