The Ontario Building Code | Fire Escape Construction
3.4.7.2. Fire Escape Construction
(1) Fire escapes shall be of metal or concrete, of the stair type extending to ground level, constructed throughout in a strong substantial manner and securely fixed to the building, except that wooden fire escapes are permitted to be used on buildingsof combustible construction if all posts and brackets are not less than 89 mm in their least dimension and all other woodwork is not less than 38 mm in its least dimension.
In Plain Language
Fire escapes must be made of metal or concrete extending to the ground and securely fixed to the building, though wood fire escapes are allowed on combustible-construction buildings if their posts and brackets meet specific size and spacing requirements.
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.