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

9.23.15.4.Direction of Installation

(1) Plywood subflooring shall be installed with the surface grain at right angles to the joists and with joints parallel to floor joists staggered. (2) OSB subflooring conforming to CSA O325, “Construction sheathing,” or to O-1 and O-2 grades in CSA O437.0, “OSB and Waferboard,” and waferboard subflooring conforming to R-1 grade in CSA O437.0 shall be installed so that the direction of face orientation is at right angles to the joists and the joints parallel to the floor joists are staggered. (See Note A-9.23.15.4.(2))
← Previous9.23.15.3. Edge SupportNext →9.23.15.5. Subfloor Thickness or Rating

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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.