The Ontario Building Code | Fire-Resistance Ratings for Walls, Columns and Arches
9.10.8.3. Fire-Resistance Ratings for walls, columns and Arches
(1) Except as otherwise provided in this Subsection, all loadbearing walls, columns and arches in the storey immediately below a floor or roof assembly shall have a fire-resistance rating of not less than that required for the supported floor or roof assembly.