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

9.33.3.1.Indoor Design Temperatures

(1) At the outside design temperature, required heating facilities shall be capable of maintaining an indoor air temperature of not less than (a) 22°C in all living spaces, (b) 18°C in unfinished basements, (c) 18°C in common service rooms, ancillary spaces and exits in houses with a secondary suite, and (d) 15°C in heated crawl spaces.
← Previous9.33.2.1. Residential Heating SystemsNext →9.33.3.2. Outdoor Design Temperatures

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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.