The Ontario Building Code | Fire Blocks in Crawl Spaces
3.1.11.6. Fire Blocks in Crawl Spaces
(1) A crawl space that is not considered as a basementby Article 3.2.2.9. and in which sprinklers are not installed, shall be separated by construction conforming to Article 3.1.11.7. into compartments not more than 600 m2 in area with no dimension more than 30 m.
In Plain Language
A crawl space that isn't treated as a basement and isn't sprinklered must be divided by fire-blocking construction into compartments no larger than 600 m², with no dimension exceeding 30 m.
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.