The Ontario Building Code | Prevention of Firewall Collapse
(1) Except as permitted by Sentence (2), the connections and supports for structural framing members that are connected to or supported on a firewall and have a fire-resistance rating less than that required for the firewall, shall be designed so that the failure of the framing systems during a fire will not affect the integrity of the firewall during the fire.
(a) a fire separation having one-half of the fire-resistance rating required for the firewall by Sentences 184.108.40.206.(1) and (2), and
(3) A firewall is permitted to be supported on the structural frame of a building of noncombustible construction provided the supporting frame has a fire-resistance rating not less than that required for the firewall.
(4) Piping, ducts and totally enclosed noncombustibleraceways shall be installed so that their collapse will not cause the collapse of the firewall.