Code Library › Volume 1 › Section 3.1 — General
PART 3 — FIRE PROTECTION, OCCUPANT SAFETY AND ACCESSIBILITYUpdated for the 2024 Ontario Building Code

3.1.7.5.Rating of Supporting Construction

r1 (1) Except as permitted by Sentence (2) and by Articles 3.2.2.20. to 3.2.2.93. for mixed types of construction, all loadbearing walls, columns and arches in the storey immediately below a floor or roof assembly required to have a fire- resistance rating shall have a fire-resistance rating not less than that required for the supported floor or roof assembly. (2) Loadbearing walls, columns and arches supporting a service room or service space need not conform to Sentence (1). (3) Except as provided in Sentence (4) and except for noncombustible roof assemblies required by Clauses 3.2.2.51.(2)(c) and 3.2.2.60.(2)(c), if an assembly is required to be of noncombustible construction and have a fire- resistance rating, it shall be supported by noncombustible construction. (4) Except for portions of a building constructed in accordance with Article 3.2.2.7. that are required to be of noncombustible construction, assemblies of noncombustible construction in buildings or portions of buildings permitted to be of encapsulated mass timber construction are permitted to be supported by encapsulated mass timber construction.
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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.