The Ontario Building Code | Column Sizes
9.17.4.1. Column Sizes
(1) The width or diameter of a wood column shall be not less than the width of the supported member.
(2) Except as provided in Article 9.35.4.2., columns shall be not less than 184 mm for round columns and 140 mm by 140 mm for rectangular columns, unless calculations are provided to show that lesser sizes are adequate.
In Plain Language
Wood columns must meet the size requirements set out in this article, ensuring adequate strength for their intended load.
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.