The Ontario Building Code | Mezzanines not Considered as Storeys
18.104.22.168. Mezzanines not Considered as Storeys
(a) the suitein which it is located, where there is more than one suitein the storey, or
(b) the storeyin which it is located, in all other cases.
(2) Mezzanines shall not be considered as storeys for the purpose of determining building height where they occupy an aggregate area not exceeding 40% of the area of the room or the storeyin which they are located provided the space above the mezzaninefloor has no visual obstructions more than 1 070 mm above such floors.