The Ontario Building Code | Separation of Concealed Spaces
3.1.11.1. Separation of Concealed Spaces
(1) Concealed spaces in interior wall, ceiling and crawl spaces shall be separated from concealed spaces in exterior walls and attic or roof spaces by fire blocks conforming to Article 3.1.11.7.
In Plain Language
Concealed spaces in interior walls, ceilings, and crawl spaces must be separated from concealed spaces in exterior walls and attic/roof spaces using fire blocks that meet Article 3.1.11.7's material requirements.
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.