Code Library › Volume 1 › Section 9.33 — Heating and Air-Conditioning
PART 9 — HOUSING AND SMALL BUILDINGSUpdated for the 2024 Ontario Building Code

9.33.6.10.Warm-Air Supply Outlets and Return Inlets — General

(1) Reserved. (2) Combustible grilles, diffusers and other devices for the supply and return air openings installed in walls and ceilings shall have a flame-spread rating of (a) not more than 200 in bathrooms, and (b) not more than 150 in rooms or spaces other than bathrooms.
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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.