What Are the Parts of Stairs?

Whether simple or complex, most stairs have the same basic components.

The creation of a staircase and its style depends on how and where the stairs are to be used. However, linear staircases generally have the same basic components: stringers, treads and risers. Other elements may be added as well.

Stringer

On these stairs, the stringers are visible below the handrails.

A stringer is a solid piece of linear lumber that generally spans the entire length of the staircase. A staircase will have a stringer on both sides to provide form, and some have one or more stringers concealed underneath to support the weight of traffic up and down the stairs. Spiral staircases instead have a helix or central column and balusters in place of stringers, but those are not as common in residential applications.

Treads

This open-style staircase has only two stringers and treads.

The treads are the planks that lay horizontally on the stringers and form the actual walking surface for the stairs. Though widths vary, most treads are 10 inches wide to provide a safe walking surface.

Risers

These risers are painted to match the surrounding walls.

The riser is the vertical plane of wood that attaches to the stringer. Most risers are about 7 inches wide, so on a typical step you move up or down 7 inches. Though risers may provide some additional load-bearing support for the treads, they mostly serve a cosmetic function by providing a surface that can be carpeted or stained to complete the stairs.

Tread Bullnose

An example of stairs with bullnose treads.

On some staircases, the the width of the treads extend over the risers by about an inch with a protruding rounded edge. This is called a bullnose.

Runners

Carpet stair runners add safety and beauty to stairs.

Interior hardwood stairs that are not carpeted are often covered with a runner. A runner is a long rectangular rug that runs down the center of the entire length of the staircase, but not necessarily the entire width. These rugs can be cut to a custom length and are used to make hardwood stairs less slippery and avoid deep scratches in the wood, or to simply add beauty. Some people choose to install runners with rods that span the width of the stairs at the lower corner where the riser meets the tread.

Handrails and Supports

In some cases, stairs are flanked by a handrail on one or both sides. The handrail may be mounted to an adjacent wall with brackets or supported from the stringer with balusters.

References

• Popular Mechanics: How to Build Stairs
• StairRunners.us
• Bullnose Tread