Ontario Building Code Practice Exam 2026 – All-in-One Guide to Master the Code!

The minimum height required for a guardrail on a balcony in a commercial building is 1100 mm. This height is determined by building codes and safety regulations, which prioritize the safety of individuals using the balcony. Option A (900 mm) and B (1000 mm) are too low and do not provide adequate protection against falls. Option D (1200 mm) is higher than the minimum requirement and may not be necessary for all commercial buildings. Therefore, option C is the most appropriate and safest height for a guardrail on a balcony in a commercial building.