The Ontario Building Code | Drainage of Vent Pipes
7.5.6.1. drainage of vent pipes
(1) Every vent pipe shall be installed without depression in which moisture can collect.
(2) Every waste pipe shall be installed and back vented at the same time.
In Plain Language
Vent pipes must be arranged so they drain back into the drainage system rather than collecting standing water or condensation, keeping the vent path clear and functional.
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.