Staircase Glossary of Terms

The humble staircase can open up a wealth of terminology that can cause confusion.

The diagram below highlights the core components of a staircaseStaircase Glossary of Terms.



















Key components

Strings: A span of timber to which treads and risers are attached to support a flight or run of stairs

Tread: The horizontal part of the stair that is stepped on.

Risers: The vertical part of the stair (where no risers are present this would be referred to as “open risers”).  The number of steps in a staircase is counted by the number of risers, not the number of treads.

Balustrade:  A row of balusters (spindles) topped by a handrail serving as a safety guarding and along the edge of a staircase.

Handrail: Following the staircase to support and guide during ascending or descending a staircase and an element to grasp in case of a fall

Newel: A large baluster or post acting as a structural element to anchor the balustrade to the floor or stair.

Spandrel: The triangular space underneath a staircase (when there is not another flight underneath).

Winder: A stair that is narrower on one side to enable a turn in the staircase.  A series of winders form a circular or spiral stairway. When three steps are used to turn a 90° corner, the middle step is called a kite winder as a kite-shaped quadrilateral.

Apron: A facia covering the ends of rough strings, carriage pieces, and the joists of landings.

Other key terms:

Flight:  An uninterrupted series of steps.

Rise: The height of an individual step (i.e. this differes from the hight of a riser as it refers to the height that must be stepped)

Going:  The depth of an individual step

Pitch: The slope of the staircase measured as the ratio between the rise and going

Walkline:  The path that an individual would follow up or down a staircase


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