The Ontario Building Code | Combustion Air
188.8.131.52. Combustion Air
(1) Every solid fuel-fired fireplace, including a factory-built fireplace, shall have a supply of combustion air from outdoorref ="http://thehandyforce.com/doors/" title ="Toronto Door installer">doors in accordance with Sentences (2) to (7).
(2) The combustion air shall be supplied by a noncombustibleand corrosion-resistant supply duct.
(3) The supply duct shall have,
(a) a diameter of not less than 100 mm or equivalent area, and
(5) The operating mechanism shall clearly indicate the actual position of the damper.
(6) The interior outlet shall,
(7) Where a supply of combustion air is provided directly to the fire chamber of a fireplace, including a factory-built fireplace or a steel fireplace liner, the installation shall comply with the "outdoorref ="http://thehandyforce.com/doors/" title ="Toronto Door installer">door Air Supply" requirements provided in CAN/CSA-A405-M, "design and Construction of masonry Chimneys and fireplaces".
9.22.2. fireplace Liners