9.22.

(1) Except as otherwise specifically stated in this Part, this Section applies to masonry fireplaces constructed on site.

(1) Except as otherwise stated in this Section, unit masonry shall conform to Section 9.20. and concrete to Section 9.3.

(2) Masonry above openings shall be supported by steel lintels conforming to Sentence 9.20.5.2.(2)v1, reinforced concrete or a masonry arch.

(1) Footings for masonry and concrete fireplaces shall conform to Section 9.15.

(1) Every solid fuel-fired fireplace, including a factory-built fireplace, shall have a supply of combustion air from outdoors in accordance with Sentences (2) to (7).

(2) The combustion air shall be supplied by a noncombustible and corrosion-resistant supply duct.

(3) The supply duct shall have,

(a) a diameter of not less than 100 mm or equivalent area, and

(b) an exterior intake for entry of air from the outdoors.

(4) The supply duct shall contain a tight-fitting damper that shall be located close to the interior outlet and be operable from the room containing the fireplace.

(5) The operating mechanism shall clearly indicate the actual position of the damper.

(6) The interior outlet shall,

(a) be located as close as possible to the opening in the face of the fireplace, and

(b) be designed to prevent embers from entering the supply duct.

(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 “Outdoor Air Supply” requirements provided in CAN/CSA-A405-M, “Design and Construction of Masonry Chimneys and Fireplaces”.

(1) Except where a fireplace is equipped with a steel liner, every fireplace shall have a firebrick liner.

(1) Fireplace liners shall be not less than,

(a) 50 mm thick for the sides and back, and

(b) 25 mm thick for the floor.

(2) Firebrick liners shall be laid with high temperature cement mortar conforming to CAN/CGSB- 10.3, “Air Setting Refractory Mortar”.

(3) Joints between a firebrick liner and the adjacent back-up masonry shall be offset.

(1) Steel liners for fireplaces shall conform to CAN/ULC-S639M, “Steel Liner Assemblies for Solid-Fuel Burning Masonry Fireplaces”, and shall be installed in accordance with the installation instructions in that standard.

(1) Except as provided in Sentence (2), the thickness of the back and sides of a fireplace, including the thickness of any firebrick liner, shall consist of not less than 190 mm thick where a metal liner or a firebrick liner less than 51 mm is used.

(2) When a steel fireplace liner is used with an air circulating chamber surrounding the firebox, the back and sides of the fireplace shall consist of,

(a) solid masonry units not less than 90 mm thick, or

(b) hollow masonry units not less than 190 mm thick.

(1) The distance from the back of the fire chamber to the plane of the fireplace opening shall be not less than 300 mm.

(1) Except as required in Sentence (2), fireplaces shall have a noncombustible hearth extending not less than 400 mm in front of the fireplace opening measured from the facing, and not less than 200 mm beyond each side of the fireplace opening.

(2) Where the fire chamber floor is elevated more than 150 mm above the hearth, the dimension of the hearth measured perpendicular to the plane of the fireplace opening shall be increased by not less than,

(a) 50 mm for an elevation above 150 mm and not more than 300 mm, and

(b) an additional 25 mm for every 50 mm in elevation above 300 mm.

(1) Except as permitted in Sentence (2), the fire chamber floor and hearth shall be supported on a reinforced concrete slab not less than a 100 mm thick at its supports and, if cantilevered, not less than 50 mm thick at its unsupported edge.

(2) A hearth for a fireplace with an opening raised not less than 200 mm from a combustible floor is permitted to be supported on that floor provided the requirements of Clauses 5.3.6.5. to 5.3.6.7. of CAN/CSA-A405-M, “Design and Construction of Masonry Chimneys and Fireplaces”, are followed.

(1) The throat of every fireplace shall be equipped with a metal damper sufficiently large to cover the full area of the throat opening.

(1) The sides of the smoke chamber connecting a fireplace throat with a flue shall not be sloped at an angle greater than 45° to the vertical.

(1) The thickness of masonry walls surrounding the smoke chamber shall be not less than 190 mm at the sides, front and back, except that the portions of the back exposed to the outside may be 140 mm thick.

(1) Factory-built fireplaces and their installation shall conform to CAN/ULC-S610-M, “Factory-Built Fireplaces”.

(1) Combustible material shall not be placed on or near the face of a fireplace within 150 mm of the fireplace opening, except that where the combustible material projects more than 38 mm out from the face of the fireplace above the opening, such material shall be at least 300 mm above the top of the opening.

(1) Metal exposed to the interior of a fireplace such as the damper control mechanism shall have at least a 50 mm clearance from any combustible material on the face of the fireplace where such metal penetrates through the face of the fireplace.

(1) Not less than a 100 mm clearance shall be provided between the back and sides of a solid fuel burning fireplace and combustible framing, except that a 50 mm clearance is permitted where the fireplace is located in an exterior wall.

(2) Not less than a 50 mm clearance shall be provided between the back and sides of the smoke chamber of a solid fuel burning fireplace and combustible framing, except that a 25 mm clearance is permitted where the fireplace is located in an exterior wall.

(1) The clearance of combustible material above heat circulating duct openings from those openings shall be not less than,

(a) 300 mm where the combustible material projects more than 38 mm from the face, and

(b) 150 mm where the projection is less than 38 mm.

(1) Fireplace inserts and hearth mounted stoves vented through the throat of a fireplace shall conform to ULC-S628, “Fireplace Inserts”.

(1) The installation of fireplace inserts and hearth mounted stoves vented through the throat of a fireplace shall conform to CAN/CSA-B365, “Installation Code for Solid-Fuel Burning Appliances and Equipment”.

(2) Fireplace inserts and hearth mounted stoves vented through the throat of a fireplace described in Sentence (1) may be installed in existing fireplaces only if a minimum thickness of 190 mm of solid masonry is provided between the smoke chamber and any existing combustible materials, unless the insert is listed for lesser clearances.

(3) A fireplace insert installed in a masonry fireplace shall have,

(a) a listed metal chimney liner installed from the insert collar to the top of the chimney, or

(b) a direct sealed connection to the chimney flue where such provision is part of an insert conforming to Sentence 9.22.10.1.(1)v1,