The Ontario Building Code | Edge Support
9.23.14.3. Edge support
(1) Where the edges of panel-type subflooring="http://thehandyforce.com/flooring/" title ="Handyman flooring install Toronto">flooring are required to be supported, such support shall consist of tongue-and-groove panel edges or not less than 38 mm by 38 mm blocking securely nailed between framing members.
In Plain Language
Subfloor panels need edge support as set out in this article, preventing unsupported panel edges from deflecting or squeaking underfoot.
This is a plain-language summary of the 2012/2017 Ontario Building Code text above, for general understanding only and not a substitute for the Code. Always confirm current requirements against the 2024 edition (O.Reg. 163/24) or a qualified professional before construction.