Do stringers count in stair width?

Staircase Construction: Do Stringers Count in Stair Width?

Summary

No, stringers typically do not count in the calculation of stair width. The width of a staircase is primarily determined by the clear space between the handrails or the finished walls on either side, excluding any protruding elements like stringers or newel posts. However, in some cases, if the stringers extend significantly beyond the handrails, they might need to be factored into the width calculation to ensure compliance with building codes and safety regulations.

Expanded Answer

Understanding how stringers impact the calculation of stair width is crucial for ensuring that your staircase meets building code requirements and provides safe and comfortable access for its users.

Stair Width Calculation

• Clear Width: The primary measurement for stair width is the clear width, which is the unobstructed space between the handrails or finished walls on either side of the staircase. This is the area where people will actually walk, so it’s important to ensure it’s wide enough for comfortable movement and meets code requirements.
• Stringer Placement: Stringers are typically positioned outside the handrails or finished walls, meaning they don’t encroach on the clear width. However, in some cases, particularly with open-sided staircases or where the stringers are unusually thick, they might extend beyond the handrails.
• Building Codes: Local building codes often dictate minimum clear widths for staircases based on various factors, including occupancy type, intended use, and number of occupants. It’s crucial to consult these codes to ensure your staircase is compliant and safe.

When Stringers Might Affect Width Calculation

• Protruding Stringers: If stringers extend significantly beyond the handrails or finished walls, they might need to be included in the width calculation. This is typically determined by local building codes, which might specify a maximum allowable projection for stringers.
• Open-Sided Staircases: In open-sided staircases without handrails on one or both sides, the stringers themselves might form the boundary of the staircase. In such cases, the distance between the stringers would need to be considered in determining the clear width.

Important Considerations:

• Consult Local Building Codes: Always refer to your local building codes for specific requirements regarding stair width and any potential impact of stringers on the calculation.
• Prioritize Safety and Accessibility: Ensure the clear width of your staircase is adequate for safe and comfortable movement, particularly during emergencies or when multiple people are using the stairs.
• Seek Professional Advice: If you’re unsure about how to measure or calculate the width of your staircase, consult a qualified building professional or architect for guidance.

Conclusion:

In most cases, stringers do not factor into the calculation of stair width, which is primarily determined by the clear space between handrails or finished walls. However, in certain situations where stringers protrude significantly or in open-sided staircases, they might need to be considered. Always adhere to local building codes and prioritize safety and accessibility when designing and constructing your staircase.