The Ontario Building Code | Protection of Non-Metallic Pipe
7.3.5.2. Protection of Non-Metallic pipe
(1) Where asbestos-cement drainage pipe or vitrified clay is located less than 600 mm below a basement floor and the floor is constructed of other than 75 mm or more of concrete, the pipe shall be protected by a 75 mm layer of concrete installed above the pipe.
In Plain Language
Non-metallic pipe such as asbestos-cement or vitrified clay drainage pipe located near other underground work needs specific protective measures, since these more brittle materials are vulnerable to disturbance.
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.