The Ontario Building Code | Solid Core Wood Door as a Closure
9.10.13.2. Solid Core wood door as a Closure
(1) A 45 mm thick solid core wood door is permitted to be used where a minimum fire-protection rating of 20 min is permitted or between a public corridor and a suiteprovided the door conforms to CAN/ulc-S113, "wood Core doors Meeting the Performance Required by CAN/ulc-S104 for Twenty Minute Fire Rated Closure Assemblies".
(2) doors described in Sentence (1) shall have not more than a 6 mm clearance beneath and not more than 3 mm at the sides and top.
In Plain Language
A solid-core wood door may serve as a closure under the specific conditions set out in this article, giving a simpler, widely available option for lower-rated fire separations.
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.