What is the difference between open and closed stringers?

Open vs. Closed Stringers: A Structural and Aesthetic Comparison

Brief Summary

The main difference between open and closed stringers lies in how they support the treads and risers of a staircase.

• Open stringers have notches cut out, allowing the treads and risers to rest visibly on top.
• Closed stringers have grooves routed into them, concealing the edges of the treads and risers for a more streamlined appearance.

Expanded Answer

Open Stringers: The Traditional Choice

• Construction: Open stringers feature notches, also known as “housings” or “mortises,” cut along their upper edge. These notches provide a resting place for the treads and risers.
• Aesthetics: The treads and risers are visible from the side, contributing to the staircase’s visual character. This design is often associated with traditional and classic styles.
• Advantages:
  • Offers a classic, timeless look
  • Easier to construct and install compared to closed stringers
  • Can accommodate various tread and riser designs
• Considerations:
  • Notches can weaken the structural integrity of the stringer, especially if not properly designed or cut.
  • Exposed treads and risers may collect dust and debris, requiring more frequent cleaning.

Closed Stringers: A Modern Aesthetic

• Construction: Closed stringers have grooves or “dadoes” routed into their inner faces to house the treads and risers. The edges of the treads and risers are concealed within these grooves, creating a clean and seamless look.
• Aesthetics: The hidden treads and risers create a modern, minimalist appearance, often favored in contemporary homes.
• Advantages:
  • Streamlined and elegant look
  • Easier to clean due to concealed edges
  • Can enhance the sense of openness in a space
• Considerations:
  • Requires more precise fabrication and installation than open stringers.
  • Can be more expensive due to additional labor and material costs.

Building Codes & Trends

• Structural Integrity: Both open and closed stringers must be designed and constructed to meet building code requirements for strength and safety. This includes ensuring proper dimensions, material choices, and attachment methods.
• Design Trends: Open risers (no vertical boards between treads) are often paired with closed stringers to create a contemporary, floating staircase effect.
• Material Choices: Stringers can be made of various materials, including wood, steel, or concrete. The choice of material impacts both aesthetics and structural performance.

Conclusion

The choice between open and closed stringers depends on your design preferences, budget, and the overall aesthetic of your home. Open stringers offer a traditional and accessible construction method, while closed stringers provide a modern and streamlined appearance. By understanding the differences between these two options and considering their pros and cons, you can make an informed decision that complements your staircase design and meets your functional and aesthetic needs.