A chimney inspection is not one fixed procedure. The depth of the work depends on why it is being done. In Canada the framework most inspectors describe to homeowners mirrors NFPA 211 in the United States, sorted into three levels, while the installation and clearance rules themselves come from the CSA B365 standard for solid-fuel appliances.
The three inspection levels
The level system is a way of matching effort to risk. A routine seasonal check is not the same as the investigation needed after a chimney fire.
Level 1 — readily accessible
This is the baseline check for a system in continued service under the same conditions. The inspector reviews the readily accessible portions of the chimney and the connected appliance: the visible flue, the connector pipe, the firebox, and the parts of the structure that can be reached without tools. It confirms the chimney is sound, free of obstruction, and reasonably free of combustible deposits.
Level 2 — on sale, change, or after an event
A Level 2 inspection is warranted whenever something changes. Common triggers include the sale or transfer of a property, a change of fuel or appliance, or any event that may have damaged the chimney — an earthquake, a building fire, or a chimney fire. It adds accessible attics, crawl spaces, and basements to the scope, and typically includes a video scan of the flue interior. No demolition is involved.
Level 3 — when concealed areas must be opened
A Level 3 inspection is reserved for cases where a serious hazard is suspected and the only way to confirm it is to open up concealed areas — removing a section of wall, ceiling, or chimney crown. Because it is destructive, it is used sparingly and only when Level 1 or 2 findings point to a hidden problem.
Which level do you need? If nothing has changed and the system is in regular use, an annual Level 1 with cleaning is the usual routine. If you are buying a house with a wood appliance, or you have just had a chimney fire, ask specifically for a Level 2.
Where WETT certification fits
WETT stands for Wood Energy Technology Transfer. It is a training and certification program for technicians who work with residential wood-burning systems in Canada, administered through WETT Inc. A WETT-certified inspector has completed coursework on the installation and inspection of wood appliances and is expected to assess a system against the relevant CSA standards.
Insurers and lenders frequently ask for a WETT inspection report when a property has a wood stove or fireplace, particularly at the point of sale. The report documents the appliance, its installation, and any clearances or deficiencies the inspector observed. It is worth noting that "WETT-certified" describes the person, not a separate inspection level; a WETT inspector still works within the Level 1–3 framework above.
- The credential applies to the technician, not the appliance.
- A typical pre-sale report is a visual assessment of installation and clearances.
- Find a certified professional through the WETT Inc. directory rather than by credential claims alone.
Hearth clearances and floor protection
Clearance to combustibles is the single most common installation problem found during inspections. The required distances are not a matter of opinion: they are set first by the appliance's own certification label, and otherwise by CSA B365. The label always governs — a certified appliance may be approved for reduced clearances that a generic rule would not allow.
Two distances matter most:
| Item | What it governs | Where the number comes from |
|---|---|---|
| Clearance to combustibles | Distance from the appliance and connector to walls, mantels, and framing | Appliance label first; otherwise CSA B365 |
| Floor protection | Size and rating of the pad beneath and in front of the appliance | Appliance label and CSA B365 |
| Connector pipe | Maximum length, slope, and clearance of the stovepipe to the chimney | CSA B365 and the manufacturer's instructions |
Do not estimate clearances. If the appliance label is missing or unreadable, an inspector will fall back to the more conservative CSA default rather than guess. Reduced-clearance shields change the math, and they only count when installed exactly as specified.
Preparing for an inspection
A few practical steps make the visit faster and the report more useful:
- Let the appliance go cold for at least a day before the appointment.
- Find the appliance label and any installation paperwork; a make and model speeds up clearance checks.
- Clear access to the appliance, the connector pipe, and — for a Level 2 — the attic or crawl space the chimney passes through.
- Note anything unusual: smoke spillage into the room, a strong odour, or a recent loud event in the chimney.
Related notes
Buildup found during an inspection is covered in the creosote removal guide. Reducing how fast that buildup forms starts with dry fuel, covered in the firewood seasoning guide.
Sources: NFPA (NFPA 211 inspection levels), WETT Inc., CSIA, and Natural Resources Canada. Verify current code requirements with your local authority having jurisdiction.