riser

In a staircase, the riser is the vertical board that forms the face of each step, bridging the gap between the tread of one step and the tread above it. It is the surface you see when you look at a flight of stairs from the side; the tread is what you step on. Together, the tread and riser make up the visible structure of a step.

Risers are typically made from softwood like pine or hardwood like oak, and must be cut to height and fitted snugly between the stringers (the diagonal structural members that support the treads). Standard riser height in residential building is around 7 to 8 inches, though building codes vary by jurisdiction and allow some variation. A taller riser can make a staircase feel steeper; shorter risers feel easier to climb.

The riser performs both functional and safety roles. It prevents objects from falling through gaps between steps and helps stiffen the staircase structure laterally. In open staircases without risers, gaps between treads can create a safety hazard and feel unstable underfoot. Many building codes require risers or specify maximum gaps if they are omitted.

Installation and Problem Areas

Risers are glued and nailed to the stringers, typically from behind so fasteners are hidden. Poor fit between riser and tread allows moisture to accumulate in the joint, leading to rot and decay. Seasonal wood movement can cause risers to separate from the treads, creating gaps that catch toes and accumulate dirt. Squeaky stairs often result from loose risers rubbing against stringers or treads.

In modern production, risers are sometimes omitted entirely in residential stairs to create a lighter, more open appearance. This is permitted by code in many areas if the gaps are measured and comply with regulations. The term open riser staircase describes this design, though it requires careful measurement and acceptance that small objects or a child's head could pass through the openings.