The Ontario Building Code | Solid Core Wood Door as a Closure 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.