Code Library › Volume 1 › Section 9.23 — Wood Frame Construction
PART 9 — HOUSING AND SMALL BUILDINGSUpdated for the 2024 Ontario Building Code

9.23.15.7.Lumber Subflooring

(1) Lumber subflooring shall be laid at an angle of not less than 45° to the joists. (2) Lumber subflooring shall be fully supported at the ends on solid bearing. (3) Lumber for subflooring shall be of uniform thickness and not more than 184 mm wide.
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What stud size and spacing does the Ontario Building Code require for walls?What are the notching and drilling limits for floor joists in Ontario?What are the wall bracing and sheathing requirements for houses in Ontario?

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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.