Ontario Building Code Practice Exam

What is the minimum height required for a guardrail on a stairway in a residential building?

1. 900 mm

2. 850 mm

3. 950 mm

4. 1050 mm

The correct answer is: 900 mm

In residential buildings, the Ontario Building Code specifies that the minimum height for a guardrail on a stairway is required to be 900 mm (millimeters). This height is designed to provide sufficient protection against falling and to ensure safety for individuals using the stairs. A guardrail at this height effectively offers a barrier that helps prevent accidental slips or missteps, especially on staircases, where the risk of falling can be higher. The 900 mm measurement is considered adequate for the majority of users, including adults and children, creating a balance between safety and functionality. Other height options, such as 850 mm, 950 mm, or 1050 mm, either do not meet the minimum requirements set by the code or exceed the necessary height for effective safety without being impractical. Therefore, adhering to the 900 mm standard is crucial for compliance with safety regulations in residential stairway design.