Code Library › Volume 1 › Section 9.22 — Fireplaces
PART 9 — HOUSING AND SMALL BUILDINGSUpdated for the 2024 Ontario Building Code

9.22.2.2.Firebrick Liners

(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 backing masonry shall be offset.
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Code text is reproduced for reference from the Ontario Building Code (O. Reg. 163/24, 2024 Building Code Compendium). This page is provided for general information and is not an official copy. Always verify requirements against the official Ontario Building Code and confirm with your local building department.