The Ontario Building Code | Blocking
9.27.5.2. Blocking
(1) Blocking for the attachment of cladding shall be not less than 38 mm by 38 mm lumber securely nailed to the framing and spaced not more than 610 mm o.c.
In Plain Language
Blocking, solid wood or other material added within the wall framing, is required as set out in this article to provide secure attachment points for cladding or trim.
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.