WETT Inspection
What a WETT Inspection Covers and When You Need One
A breakdown of the Wood Energy Technology Transfer inspection process, what inspectors look for, and how it connects to home insurance requirements in Canada.
Fireplace & Wood Stove Safety — Canada
Know Your Chimney Before Winter Arrives
WETT inspection schedules, creosote build-up indicators, hearth clearance codes, and chimney relining options — explained clearly for residential property owners across Canada.
Reference Articles
Core Topics in Chimney & Hearth Safety
Three in-depth guides covering the most common questions Canadian homeowners have about wood-burning systems.
Creosote Removal
Creosote Stages, Removal Methods, and Prevention
How creosote accumulates in flues, the difference between Stage 1 and Stage 3 deposits, and which removal procedures apply to each level of build-up.
Chimney Relining
Chimney Liner Types: Stainless Steel, Cast-in-Place, and Clay Tile
A comparison of relining materials and methods — including when each option is appropriate and how Canadian building codes affect liner selection.
Chimney fires are preventable — most start with creosote left unaddressed for a season
According to the National Fire Protection Association, heating equipment — including fireplaces and wood stoves — accounts for a significant share of residential fires in North America. Annual cleaning and a scheduled WETT review remain the two most effective countermeasures.
Read: Creosote RemovalSafety Fundamentals
Four Aspects Every Wood-Burning Homeowner Tracks
Annual Flue Inspection
A WETT-certified technician examines the flue liner, smoke chamber, damper, and firebox for cracks, blockages, or deterioration that could allow combustion gases to enter living spaces.
Creosote Cleaning Schedule
Deposits form whenever wood smoulders at low temperatures. A chimney swept once a year — before the burning season — keeps Stage 1 accumulation from progressing to the harder, glazed Stage 3 variety.
Hearth Clearance Codes
The CSA B365 installation standard specifies minimum clearances between combustible materials and any solid-fuel appliance. These distances differ by appliance type, fuel type, and local municipal overlays.
Liner Condition
Clay tile liners in older homes develop cracks over decades of thermal cycling. A deteriorated liner allows superheated gases to contact the surrounding masonry — one of the primary chimney fire risk factors.
Seasoned Wood Only
Wood with a moisture content above 20% burns inefficiently and deposits far more creosote than properly dried hardwood. A simple pin-type moisture meter — available at most hardware stores — removes the guesswork.
Insurance Documentation
Several Canadian insurers require a current WETT inspection certificate when a wood-burning appliance is present. Keeping a copy on file before policy renewal avoids coverage gaps or premium adjustments.
CSA B365
The Canadian installation standard covering solid-fuel-burning appliances — referenced by WETT inspectors and required for building permit compliance nationwide.
ULC S109 / ULC S610
Standards governing chimney liner materials in Canada. Stainless steel liners must meet ULC S635; factory-built chimneys carry their own ULC listing numbers.
National Building Code
Part 9 of the NBC addresses residential heating appliances. Provincial and territorial editions introduce local amendments that override the base document in specific situations.
Hearth clearance distances are not uniform across Canada
The base CSA B365 distances apply nationally, but Alberta, British Columbia, and Ontario each publish provincial amendments. A clearance that meets code in one province may fall short in another. Always verify against the local authority having jurisdiction (AHJ) before installation or renovation.
Read: WETT Inspection GuideWood stove efficiency ratings and what they mean for your fuel costs
EPA Phase II certified stoves (2020 standard) must achieve particulate emissions below 2.0 g/hour. Higher-efficiency models convert more of the wood's energy to heat, which means less wood consumed and fewer creosote-forming incomplete combustion gases entering the flue. Older non-certified stoves installed before 1988 may not meet current provincial air-quality regulations in B.C. and Ontario.
Environment and Climate Change Canada — Wood Burning Information →
Get in Touch
Questions About Your Chimney or Hearth
Open Hearth Co
344 Elgin Street, Suite 200
Ottawa, ON K2P 1M6
Canada
Phone: +1 (613) 555-0192
Email: info@openhearthco.org
Business registration: ON Corp. #1187452
This resource does not provide certified inspection or installation advice. For a WETT inspection, contact a WETT-certified technician in your area.