The Ontario Building Code | Crack Control Joints
9.15.4.9. Crack Control Joints
(1) Crack control joints shall be provided in foundationwalls more than 25 m long at intervals of not more than 15 m.
(2) Joints required in Sentence (1) shall be designed to resist moisture penetration and shall be keyed to prevent relative displacement of the wall portions adjacent to the joint.
In Plain Language
Crack control joints are required at intervals set out in this article, allowing a masonry or concrete foundation wall to move slightly without unsightly or structurally significant random cracking.
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.