The Ontario Building Code | Combustible Mezzanines
3.1.5.24. Combustible Mezzanines
(1) In a building required to be of noncombustible construction, a mezzaninelocated within a live/work unit is permitted to be of combustible construction, provided the area of the mezzanine is not more than 25% of the floor area of the live/work unitor 20 m2, whichever is less, and has no obstructions more than 1 070 mm above the floor.