Code Library › Volume 1 › Section 9.30 — Flooring
PART 9 — HOUSING AND SMALL BUILDINGSUpdated for the 2024 Ontario Building Code

9.30.3.1.Thickness

(1) The thickness of wood strip flooring shall conform to Table 9.30.3.1. Table 9.30.3.1. Thickness of Wood Strip Flooring Forming Part of Sentence 9.30.3.1.(1) Minimum Thickness of Flooring, mm Type of Flooring Maximum Joist Spacing, mm With Subfloor No Subfloor Matched hardwood 400 7.9 19.0 (interior use only) 600 7.9 33.3 Matched softwood 400 19.0 19.0 (interior or exterior use) 600 19.0 31.7 Square edge softwood 400 — 25.4 (exterior use only) 600 — 38.1

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.