The Ontario Building Code | Offsetting of Joints
9.27.7.4. Offsetting of Joints
(1) In single-course application, joints in succeeding courses shall be offset at least 40 mm so that joints in any two of three consecutive courses are staggered.
(2) In double-course application, joints in the outer course shall be offset from joints in the under-course by not less than 40 mm, and joints in succeeding courses shall be offset not less than 40 mm.
In Plain Language
Joints in this cladding must be offset from course to course, as set out in this article, avoiding a continuous vertical seam that could let water through more easily.
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.