Where a handrail is provided on one side of the stairway what is the minimum required clear width at and below the handrail height?
Minimum Clear Stairway Width with a Single Handrail: Building Code Requirements
Summary
When a handrail is installed on only one side of a stairway, the minimum required clear width at and below the handrail height, including treads and landings, must be at least 31.5 inches (787 mm). This requirement ensures sufficient space for safe movement and accessibility, even with the presence of the handrail.
Detailed Explanation
Understanding Clear Width Requirements
Clear width refers to the unobstructed space available for passage on a stairway. Building codes stipulate minimum clear width requirements to ensure that stairways are safe and accessible for all users, including those with mobility challenges or carrying objects.
Importance of Clear Width at Handrail Height
The specific requirement for clear width at and below the handrail height recognizes that handrails can project into the stairway, potentially reducing the available space for movement. By specifying a minimum clear width even with the handrail in place, building codes ensure that users have adequate room to comfortably and safely use the stairs.
Key Code Requirements
- International Residential Code (IRC): The IRC, a widely adopted building code in the US, states that the minimum clear width of a stairway at and below the handrail height shall be not less than 31.5 inches (787 mm) when a handrail is installed on one side.
- Local Building Codes: While the IRC serves as a baseline, it’s important to consult local building codes for any specific requirements or variations in your jurisdiction.
Implications for Staircase Design
- Handrail Placement: When designing a stairway with a single handrail, ensure that the chosen width allows for at least 31.5 inches of clear space at and below the handrail height, even after accounting for the handrail projection.
- Staircase Width: If the overall stairway width is limited, consider alternative handrail designs or configurations that minimize projection into the clear space.
- Accessibility: In situations where accessibility is a concern, it’s crucial to verify compliance with additional accessibility standards, which may require wider clear widths even with a single handrail.
Conclusion
The minimum required clear width of 31.5 inches with a single handrail ensures that stairways remain safe and accessible, even with the presence of the handrail. Adhering to this requirement and any additional local building codes will help create a staircase that meets both functional and safety standards.