The Ontario Building Code | Screwed Joints
7.3.2.3. Screwed Joints
(1) In making a screwed joint, the ends of the pipe shall be reamed or filed out to the size of the bore and all chips and cuttings shall be removed.
(2) No pipe-joint cement or paint shall be applied to the internal threads.
In Plain Language
When making a screwed (threaded) pipe joint, the pipe ends must be properly reamed and cleared of chips and cuttings so the connection is smooth and doesn't restrict flow.
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.