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

9.8.4.1.Dimensions for Risers (See Note A-9.8.4.)

(1) Except as provided in Article 9.8.4.7., the rise, which is measured as the vertical nosing-to-nosing distance, shall conform to Table 9.8.4.1. Table 9.8.4.1. Rise for Rectangular Treads, Tapered Treads and Winders and Run for Rectangular Treads Forming Part of Sentences 9.8.4.1.(1) and 9.8.4.2.(1) Max. Rise, mm, for Min. Rise, mm, for Max. Run, mm, for Min. Run, mm, for Stair Type All Steps All Steps Rectangular Treads Rectangular Treads Private stairs(1) 200 125 355 255 Public stairs(2) 180 125 no limit 280 Service stairs(3) no limit 125 355 no limit Stairs to unoccupied attic space(4) no limit 125 355 no limit Stairs to crawl spaces no limit 125 355 no limit Stairs that serve mezzanines not no limit 125 355 no limit exceeding 20 m2 within live/work units Notes to Table 9.8.4.1.: (1) Private stairs are: (a) interior stairs within a house with a secondary suite or an individual dwelling unit, (b) exterior stairs serving a house with a secondary suite or an individual dwelling unit, and (c) exterior stairs serving a garage that serves a house with a secondary suite or an individual dwelling unit. (2) Public stairs are all stairs not described as service stairs or private stairs. (3) Service stairs are stairs that serve areas used only as service rooms or service spaces. (4) Stairs to unoccupied attic space are stairs that serve attics containing no storage or living space.

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

← Previous9.8.3.3. Maximum Height of StairsNext →9.8.4.2. Dimensions for Rectangular Treads (See Note A-9.

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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.