Ontario Building Code Practice Exam 2025 - Free Building Code Practice Questions and Study Guide

The requirement for a fire-rated wall assembly in an industrial building is governed by standards intended to enhance safety by preventing fire spread. A fire-rated wall assembly must indeed be constructed of non-combustible materials, which are essential for maintaining the integrity of the wall during a fire. Additionally, such assemblies need to have a clear fire rating label, which communicates the time duration they can withstand fire exposure, and they must be continuous from floor to underside of the roof sheathing to ensure there are no gaps that could allow fire to spread.

The specification of a minimum thickness, like 75 mm, is not universally mandated for fire-rated wall assemblies. Instead, the thickness depends on the specific fire-resistance rating required for the project and the materials used. Therefore, thickness can vary greatly and is determined by various factors, including local regulations and the assembly's overall design criteria. As a result, stating a fixed minimum thickness does not align with the variability and requirements set out in fire safety codes.