In Plain Language

Except for outlet pipes installed under specific alternative provisions, fixture outlet pipes have a maximum length, since a run that's too long can let waste settle and slow or block the flow before it reaches the main drain.

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.