Code Library › Volume 1 › Section 9.8 — Stairs, Ramps, Handrails and Guards
PART 9 — HOUSING AND SMALL BUILDINGSUpdated for the 2024 Ontario Building Code

9.8.2.1.Stair Width

(1) Except as provided in Sentence (2) and Article 9.8.4.7., required exit stairs and public stairs serving buildings of residential occupancy shall have a width of not less than 900 mm. (2) Exit stairs serving a single dwelling unit or a house with a secondary suite including their common spaces shall have a width of not less than 860 mm. (3) Except as provided in Article 9.8.4.7., required exit stairs and public stairs serving buildings of other than residential occupancy shall have a width of not less than the greater of (a) 900 mm, or (b) 8 mm per person based on the occupant load limits specified in Table 3.1.17.1. (4) Except as provided in Article 9.8.4.7., at least one stair between each floor level within a dwelling unit, and exterior stairs serving a single dwelling unit except required exit stairs, shall have a width of not less than 860 mm.

This provision includes a table — formatting is preserved from the source; refer to the official code for the authoritative layout.

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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.