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

3.1.11.7.into compartments that are

(a) not more than 600 m2 in area with no dimension more than 60 m, if the exposed construction materials within the space have a flame-spread rating not more than 25, and (b) not more than 300 m2 in area with no dimension more than 20 m, if the exposed construction materials within the space have a flame-spread rating more than 25. (See Note A-3.1.11.5.(3) and (4)) (5) Fire blocks conforming to Sentences (3) and (4) are not required where the horizontal concealed space within the floor or roof assembly is entirely filled with noncombustible insulation such that any air gap between the top of the insulation and the floor or roof deck does not exceed 50 mm.
← Previous3.1.11.5. Fire Blocks in Horizontal Concealed SpacesNext →3.1.11.6. Fire Blocks in Crawl Spaces

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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.