Stair Glossary

Short for compliance with the Americans with Disabilities Act, the set of accessibility standards public and commercial stairs have to meet: minimum widths, handrail heights, and slip-resistant treads among them. It applies most directly to commercial stairs, not typical residential builds.

One of the vertical spindles running between the handrail and the treads, spaced to meet code and to fill out the look of the railing. Baluster style and spacing are part of every stair railing installation.

The full railing assembly, handrail, balusters, and newel posts together, rather than any one piece of it. A mismatched balustrade is one of the more common reasons clients call about stair railings & handrails.

Stairs leading down from a deck, porch, or elevated exterior surface, built to the same code baseline as interior stairs with weather and material considerations layered on top. See outdoor stairs for what changes outside.

The code term for a safe path out of a building, stairs included; egress requirements are where commercial stair code gets strictest. It's a central concept in commercial staircase work.

A staircase built to hide its own structure, usually a single steel stringer with treads cantilevered off it, so the run appears to hang in open air. Browse floating staircase projects to see the structure explained.

The barrier along the open side of a stair, landing, or elevated deck, taller than a handrail because its job is fall protection rather than something to grip while climbing. Guard height is one of the two figures people usually mean when they ask about stair railing height code.

The rail mounted at hand height along a stairway, meant to be gripped while climbing rather than to stop a fall. Handrail material, wood, cable, or welded steel, gets decided as part of handrail installation.

The clear vertical space above a stair, measured from the tread nosing to whatever sits overhead, usually the ceiling or the underside of the flight above. Headroom is one of the dimensions checked against Oregon stair code on any new build.

A flat platform between flights of stairs, or at the top or bottom of a run, used to break up a tall staircase or change its direction. Landings come up often on custom stair builder projects connecting more than one floor.

The main post anchoring a stair railing at the top and bottom of a run, carrying most of the structural load the rest of the balustrade puts on it. Newel style, whether wood, welded metal, or paired with a cable railing system, gets decided as part of that same design conversation.

The rounded or projecting front edge of a tread, the part your foot catches first on each step. Tread nosing is the reference point for several measurements in code requirements, including headroom and riser height.

The overall steepness of a staircase, set by the relationship between riser height and tread depth across the full run. A stair cost calculator estimate typically starts from pitch, since it drives how many steps a given rise needs.

The vertical section between two treads, closing the gap a tread would otherwise leave open. Riser height is one of the first things that gets reworked on a stair replacement.

The horizontal depth of a single tread, measured front to back, sometimes shortened to "run" to distinguish it from the vertical rise. Run and riser height together set the pitch of any staircase, which is exactly what changes on a project to replace your stairs.

A staircase that winds around a central pole in a tight, compact footprint, trading floor space for a smaller footprint than a curved or straight run. See modern staircase design for how a spiral compares to a curved run.

The complete structure connecting two levels: stringers, treads, risers, and railing together, not any single component of it. A full custom staircase design & build starts with the staircase as a whole rather than one piece at a time.

The structural frame that carries the treads and risers, cut from wood or fabricated from steel depending on the design. Welded steel stringers are where steel & metal stairs construction is most visible.

The horizontal surface you step on, the part of the staircase that takes the direct wear. Worn or damaged treads are one of the more common reasons for a stair replacement in Portland.

A wedge-shaped tread used to turn a staircase within a landing instead of adding a separate flat landing, common in tighter stairwells. Winders show up most often on modern stairs projects working around a tight footprint.