How high is a 2 step stringer?
Understanding Stringer Height for 2-Step Stairs
How tall is a 2-step stair stringer, considering standard riser heights and building code requirements in the USA?
Brief Summary:
The overall height of a 2-step stair stringer typically ranges from 13.5 inches to 15.5 inches. This is determined by the combined height of two risers, which usually measure between 6 ¾ inches and 7 ¾ inches each according to building codes. However, specific dimensions can vary based on local regulations and individual project requirements.
Expanding the Answer: Factors Influencing Stringer Height
- Riser Height:
- Building Codes: In most regions of the USA, building codes mandate a maximum riser height of 7 ¾ inches for residential stairs. However, some areas might allow slightly higher risers, up to 8 ¼ inches, for specific applications like basement or attic stairs.
- Comfort and Safety: While codes provide a maximum limit, it’s important to consider comfort and safety when choosing riser height. A riser height between 6 inches and 7 inches is generally considered comfortable for most people.
- Tread Depth (Run):
- While not directly influencing the stringer’s height, tread depth plays a crucial role in overall stair safety and comfort. Building codes typically require a minimum tread depth of 10 inches.
- The relationship between riser height and tread depth is often expressed in the “rise + run = 17-18” rule, suggesting that the combined measurement of one riser and one tread should ideally fall within this range for optimal comfort and safety.
- Stringer Design and Material:
- Stringer Type: The type of stringer (cut stringer, housed stringer, or block stringer) can influence its overall height, particularly at the top and bottom where it connects to landings or floors.
- Material Thickness: The thickness of the stringer material will also contribute to its overall height. Common materials like 2×10 or 2×12 lumber have nominal thicknesses of 1 ½ inches and 1 ¾ inches, respectively.
Calculating Stringer Height
For a 2-step staircase with standard 7-inch risers:
- Total Rise: 2 risers x 7 inches/riser = 14 inches
- Stringer Height: Total Rise + additional height for top and bottom connections (typically 1 ½ inches to 2 inches total) = Approximately 15.5 inches to 16 inches
Code Compliance and Safety
Always prioritize safety and adherence to local building codes when constructing stairs. Even for a simple 2-step staircase, ensure the riser height and tread depth meet code requirements. Consult with local building authorities or a qualified professional if unsure about specific regulations.
Conclusion
The height of a 2-step stair stringer typically falls between 13.5 inches and 15.5 inches, depending on riser height and stringer design. While this provides a general guideline, always refer to local building codes and prioritize safety and accessibility when planning and constructing any staircase.