Stair Stringer Types

The staircase stringer is the structural member that supports the treads or risers and may be at either side of the stair, under the stair or even in the centre of the stair in the case of a mono stringer. The stringers provide the stiffness to the stairs and are very important to the structural integrity of the stair. Additionally, the choice of stringer may be used to impact the aesthetics of the stair from a purely visual perspective. At Active Metal, we use a range of different stair stringer types to complete our projects. Using advanced engineering techniques and the best materials, we can create the perfect stair design for your site. 

Our stair stringers types include:

  • Plate stringers – utilise either standard flat bar steel sections or can be profile cut to any measurement or shape from the plate material (if a unique, custom solution is required). Usually, this type of stringer provides for a space efficient design with stringers sourced from mild steel or stainless steel plates in varying sizes. 
  • Saw-tooth stringers – a type of plate stringer that is cut from flat mild steel or stainless steel plates in varying sizes (dependent on engineer’s approval and the requirements of the design).
  • Double plate or H stringers – variation of the plate or profile cut stringer, except it uses 2 plates to create an ongoing pocket for grouting glass. Note: project engineer determines plate thickness. 
  • Channel stringers – very strong and common stringer type, the PFC (parallel flanged channel) can be left exposed or it can be plated to form a narrow hollow section for extra strength. 
  • Box stringers – robust although sometimes bulky, the box stringer (also known as RHS), is a commonly used detail when it comes to the manufacture of steel stairs. These stringers are available in either rectangular or square shapes. The width of the section will often determine the final width of the stairs, so it’s important to keep in mind detailing if there is limited space to work with.