Chimney Information
CHIMNEYS
Chimneys are among the heaviest and most structurally vulnerable of all exterior components of a building. Accidents caused by their collapse can lead to death. A collapse can also cause costly structural damage to the building and its surroundings. Inspection, maintenance and preparedness are critical safeguards against chimney collapse.
BRICK CHIMNEYS
Chimneys that are one brick thick and unlined are a fire hazard and must be noted. A two-brick chimney, without a flue liner is acceptable as long as the mortar and bricks are in good condition. The majority of chimneys in Ontario are lined with clay flue tiles.
Metal flues for gas appliances such as furnaces must have a cap on them to prevent weather and animals from entering. Caps on masonry chimneys are cement/mortar and have a tendency to crack. New construction requires that the chimney cap be one piece, either bought or poured on site.
The majority of problems with chimney flues and bricks could be easily prevented with the installation of a rain cap. Preventing water from entering chimney during winter months will greatly extend the life of your chimney.
METAL CHIMNEYS
TYPES OF METAL CHIMNEYS
A Class "A" chimney is a factory built section insulated chimney constructed from stainless steel.
A Type "B" chimney is for Gas Appliances only, and is constructed from aluminum.
CLEARANCES
Metal chimneys should have enough clearance to avoid heating combustible materials to a temperature in excess of 90 degrees above the ambient temperature.
Exterior and Interior. Wood frame or other combustible material—18 inches minimum.
Exterior and Interior. Metal chimney over 18² diameter-Non combustible materials-4 inches minimum.
Exterior and Interior. Metal chimney 18² diameter or less—Non combustible materials—2 inches minimum.
Interior. Metal chimneys must be enclosed in a continuous enclosure and maintain the integrity of fire separations—1 hour rating in buildings up to 4 stories.
Fire stops at floors, walls and roofs must be made of entirely non-combustible materials. 9 inches is the typical clearance, however, it is 18 inches if galvanized steel or approved corrosion-resistant metal is not used.
When in doubt about any chimney consult with WETT Certified Inspector or Licensed Gas Technician to insure you and your families safety.
| Barrie Home Inspector | Office Phone: (705) 795-8255 |
| Stollar Blvd, Barrie | Inspection Scheduling: (888) 818-8608 |
| Alliston, Barrie, Orillia, Simcoe County | Email: Click here to contact us |
| WETT Inspections |
