The Ontario Building Code | Cavity Walls Supporting Framing Members
9.20.8.2. Cavity walls supporting Framing Members
(1) floor joists supported on cavity walls shall be supported on solid units not less than 57 mm high.
(2) floor joists described in Sentence (1) shall not project into the cavity.
(3) Roof and ceiling framing members bearing on cavity wallsshall be supported on,
(a) not less than 57 mm of solid masonry, bridging the full thickness of the wall, or
(b) a wood plate not less than 38 mm thick, bearing not less than 50 mm on each wythe.
In Plain Language
Cavity walls supporting framing members have specific requirements set out in this article, addressing how loads transfer through this two-wythe wall system.
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.