Level 1 vs. Level 2 WETT Inspections: What Does Your System Actually Need?

WETT's SITE® framework separates inspections by depth and accessibility. The purpose is to define what the inspector will examine and what remains outside the scope—not to create a universal “pass” that applies to every insurer or transaction.

Level 1 Visual Inspection: The Compliance Baseline

The Level 1 Visual Inspection is the standard entry point encountered during routine insurance renewals or real estate transactions. It serves as a non-invasive baseline to verify that the visible installation meets provincial safety codes.

• Scope of Work: The inspector focuses exclusively on "readily accessible" components. The assessment is limited to what can be seen without using tools to open panels or access concealed spaces.
• Tools Used: High-intensity flashlights, inspection mirrors, and measuring tapes to confirm strict "clearances to combustibles."

For a well-maintained, modern system, these tools are often sufficient for underwriters. However, a Level 1 report is merely a "snapshot" of visible conditions. It cannot detect internal flue cracks or hidden structural decay.

Level 2 Technical Inspection: Diagnostic Depth

When a system’s performance is in question, or a significant change occurs (like buying a century home in a historic London neighbourhood), a Level 1 check is insufficient. A Level 2 Technical Inspection shifts the scope from "Readily Accessible" to "Accessible" components.

• Scope of Work: The inspector physically interacts with the system’s architecture. This includes accessing attics and crawlspaces, and getting up on the roof to access the chimney crown and exterior vent terminals.
• Tools Used: Hand tools to remove baffles, firebricks, and gaskets to inspect for cracks, thinning metal, or failed seals, plus ladders for roof access.
• When it may be considered: A report recipient or inspector may recommend a technical scope when history is unknown, symptoms or a prior incident require investigation, components are not readily accessible, or the requested documentation exceeds a visual inspection.

The Diagnostic Escalation Trigger

If the agreed visual scope cannot adequately address an observation or accessible condition, the inspector may recommend a broader technical or invasive scope. That recommendation should explain what additional question needs to be answered.

Critical Red Flags include:

• Creosote accumulations exceeding 3mm (1/8 inch), particularly "glazed" creosote which hides structural damage.
• Cracked firebricks, compromised baffles, or failing door gaskets.
• Clearance violations or evidence of "pyrolysis" (heat damage) on nearby combustible surfaces like drywall or mantels.

Strategic Advice: When to Start at Level 2

From a financial perspective, "starting deep" is often the most cost-effective strategy. Paying for a Level 1 inspection that immediately results in a "failed" report and a recommendation for a Level 2 visit means you are paying for two separate service calls.

Ask whether a Level 2 technical inspection is appropriate if:

• You are purchasing a home with an unknown chimney maintenance history.
• The system has experienced a chimney fire in the past.
• You noticed poor performance, smoke rolling into the room, or heavy creosote production last winter.

Stop Guessing About Your Safety

The right scope is the one accepted by the report recipient and appropriate to the system's history, access, and observed condition. Use the free triage tool to organize those facts, then confirm the inspection level with the requesting party and provider.

Level comparison

Sources and limitations

• WETT Inc.: Levels of inspection
• WETT Inc.: About WETT inspections

Last reviewed: July 23, 2026. Always use WETT's current definitions and confirm the scope in writing before booking.