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

9.8.4.5.Uniformity of Runs in Flights with Mixed Treads within Dwelling Units

(1) Except as provided in Sentence (2) and Article 9.8.4.6., where a flight of stairs consists of both tapered treads and rectangular treads, all the treads shall have a uniform run when measured at a point 300 mm from the centre line of the inside handrail. (2) Where tapered treads are located at the bottom of a mixed-tread flight, the run of the tapered treads when measured at a point 300 mm from the centre line of the inside handrail is permitted to exceed the run of the rectangular treads.
← Previous9.8.4.4. Uniformity and Tolerances for Risers, Runs and TNext →9.8.4.6. Winders (See Note A-9.8.4.6.)

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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.