The Ontario Building Code | Exits from Interconnected Floor Space
3.4.3.3. Exits from Interconnected floor Space
(1) Exit stairs that serve interconnected floor spaces as provided in Articles 3.2.8.3. to 3.2.8.11. shall conform to the requirements in Article 3.2.8.4. and in this Section.
In Plain Language
Exit stairs serving an interconnected floor space (like an atrium) must meet the specific requirements cross-referenced from Subsection 3.2.8, layering additional protection onto standard exit stair rules given the added smoke-spread risk of open interconnected spaces.
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.