What are stringers in stairs?

Demystifying Staircase Stringers: The Backbone of Your Stairs

Brief Summary

Stringers are the structural, inclined boards that form the framework of a staircase, supporting the treads (horizontal steps) and risers (vertical boards between treads). They transfer the weight of the stairs and its users to the floor or supporting structure, ensuring stability and safety.

Expanded Answer

Stringers: Essential for Staircase Construction

• Function & Purpose: Stringers are the load-bearing backbone of a staircase. They provide the essential framework for attaching the treads and risers, ensuring that the staircase can safely carry the weight of people and other loads.
• Location: Typically, there are two stringers, one on each side of the staircase. In some cases, particularly for wider stairs or modern designs, a central stringer may be used for additional support or aesthetic purposes.
• Material: Stringers are commonly made of wood, such as dimensional lumber or engineered wood products (like LVL). Metal stringers, usually steel or aluminum, are also gaining popularity, especially in contemporary designs.

Types of Stringers

• Cut Stringers (or Open Stringers): These stringers have notches or “cutouts” along their upper edge to accommodate the treads and risers. They offer a traditional look where the treads and risers are visible from the side.
• Closed Stringers: These stringers have routed grooves or dadoes on their inner faces to house the treads and risers. This creates a more streamlined and modern appearance, with the treads and risers flush with the stringer’s surface.
• Mono Stringer (or Central Stringer): This design features a single, central stringer that supports the treads from underneath. This creates a visually open and floating effect, often seen in contemporary staircases.

Building Codes and Regulations

• Structural Integrity: Stringers must comply with building codes to ensure adequate strength and safety. These codes specify factors like:
  • Dimensions: The minimum width and thickness of the stringer based on the staircase’s span and anticipated loads.
  • Material: The type and grade of material used for the stringers.
  • Attachment Methods: How the treads and risers are connected to the stringers (e.g., nails, screws, or adhesives).
• Inspections: During construction or renovations, building inspectors will verify that the stringers adhere to the applicable codes.

Current Trends

• Open Risers: Modern staircase designs often favor open risers, where the space between treads is left open, creating a more airy and spacious feel. This trend places greater emphasis on the visual appeal of the stringers.
• Metal Stringers: The use of metal stringers, especially in conjunction with open risers, is becoming increasingly popular, offering a contemporary and minimalist aesthetic.
• Floating Staircases: The use of mono stringers or concealed stringers contributes to the “floating” illusion of these modern staircases, where the treads appear to be unsupported.

Conclusion

Stringers are the unsung heroes of staircase construction, providing the critical structural framework that ensures safety and stability. Understanding their types, functions, and building code requirements is vital for designing and building a durable and compliant staircase. Whether you choose traditional cut stringers, sleek closed stringers, or a modern mono stringer design, prioritize safety and structural integrity while incorporating your aesthetic preferences for a beautiful and functional staircase.