The Ontario Building Code | Roof Trusses
9.23.5.5. Roof Trusses
(1) Roof truss members shall not be notched, drilled or otherwise weakened unless such notching or drilling is allowed for in the design of the truss.
9.23.6. Anchorage
In Plain Language
Roof trusses can't be drilled, notched, or altered except as set out in this article, since trusses are engineered assemblies where field modifications can seriously compromise structural performance.
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.