Basic stairway nomanclature

  • Step: The step is composed of the tread and riser.
  • Tread: The part of the step where the foot is placed when climbing the stairway.  The tread "depth" is measured from the outer edge of the step or "nose" to the vertical "riser" between steps. The "width" is measured from one side to the other.
  • Tread Cut or Run: The actual depth of the tread less the overhang of the nose. Sometimes called the "going".
  • Riser: The vertical portion between each tread on the stair and where each time you lift your foot when climbing the stair.
  • Throat: The portion of the riser between the top of the lower tread and the bottom of the upper tread. The throat is the measurement of the rise subtracting the thickness of the tread material.
  • Total Rise: The height of the staircase from the finish floor to the finish floor of the landing and/or balcony. "Total risers" is the amount of times one will lift their foot to climb the sitars.
  • Total Run: The entire distance the staircase will travel.
  • Overhang/Nose : The edge part of the tread that protrudes over the riser beneath. If it is present, this means that, measured horizontally, the total "run" length of the stairs is not simply the sum of the tread lengths, as the treads actually overlap each other slightly.
  • Stringer, Stringer beam or sometimes just String: The structural member that supports the treads and risers and load of climbers. There are typically two stringers, one on either side of the stairs; though the treads may be supported many other ways. The stringers are sometimes notched so that the risers and treads fit into them. Stringers on open-sided stairs are often open themselves so that the treads are visible from the side. Such stringers are called "cut" stringers. Stringers on a closed side of the stairs are closed, with the support for the treads routed into the stringer or bolted onto steel.

  • Flight: A flight is an uninterrupted series of steps.

  • Stairwell: The spatial opening, usually a vertical shaft, containing an indoor stairway; but it is often used as including the stairs it contains.

  • Stair Tower:  A tower attached to, or incorporated into, a building that contains stairs linking the various floors.

  • Spandrel:  If there is not another flight of stairs immediately underneath, the triangular space underneath the stairs is called a "spandrel". It is frequently used as a closet.

  • Single Stringer Staircase:  A staircase carried by a  single beam oriented under the treads at the center of the staircase. This creates a modern look and has a lighter floating look.

  •  Mono string staircase also a single steel spine staircase .

  • Double string staircase has two steel beams on either side and treads in the center

  • Open Riser Staircase: A staircase that is open at the riser between the treads. This creates a modern look and makes the stairs partially see through.
  • Winding Staircase: Steps that are narrower on one side than the other. They are used to change the direction of the stairs without landings. A series of winders form a circular or spiral staircase. When three steps are used to turn a 90° corner, the middle step is called a kite winder because it is a kite shaped quadrilateral.  Winders may be used in combination with straight stairs to turn the direction of the stairs. This allows for a large number of permutations.
  • Floating Stairs: A flight of stairs is said to be "floating" if there is nothing underneath. The risers are typically missing as well to emphasize the open effect. There may be only one stringer or the stringers otherwise minimized.

  • Spiral Staircase: A staircase with a center point typically a post or column with winding treads installed around it to make up the staircase.  With a handrail on the outer side only, and on the inner side just the central pole. A squared spiral stair assumes a square stairwell and expands the steps and railing to a square, resulting in unequal steps (larger where they extend into a corner of the square). A pure spiral assumes a circular stairwell and the steps and handrail are equal and positioned screw symmetrically. A tight spiral stair with a central pole is very space efficient in the use of floor area. Spiral stairs have the disadvantage of being very steep. Unless the central column is very large, the circumference of the circle at the walk line will be small enough that it will be impossible to maintain a normal tread depth and a normal rise height without compromising headroom before reaching the upper floor. To maintain headroom most spiral stairs have very high rises and a very short going. Most building codes limit the use of spiral stairs to small areas or secondary usage.

  • Circular Staircase: A circular staircase unlike a spiral staircase makes a circle that is wider and is open in the center instead of traveling around a center pole. It will have railings on both sides. These stairs have the advantage of a more uniform tread width when compared to the spiral staircase. Such stairs may also be built elliptical or oval. 
  • Both spiral and helical stairs can be characterized by the number of turns that are made. A "quarter-turn" stair deposits the person facing 90 degrees from the starting orientation. Likewise there are half-turn, three-quarters-turn and full-turn stairs. A continuous spiral may make many turns depending on the height. Very tall multi-turn spiral staircases are usually found in old stone towers within church towers and in lighthou Railing Terminology


basic railing nomenclature

  • Balustrade:  is the system of railings and balusters.
  • Guard Rail: Railings that prevent people from falling over the edge.
  • Handrail or Banister The angled member for gripping,  there is often hand rail on both sides of a staircase depending on the width. on wide staircases where there is guardrail on only one side there is sometimes also wall mounted handrail on the other, one in the middle, or even more. The term "banister" is sometimes used to mean just the handrail, or sometimes the handrail and the balusters or sometimes just the balusters.
  • Volute: A handrail end element for the bull-nose step that curves inward like a spiral. A volute is said to be right or left-handed depending on which side of the stairs the handrail is as one faces up the stairs.
  • Turnout: Instead of a complete spiral volute, a turnout is a quarter-turn rounded end to the handrail.
  • Lambs Tongue:: A forged hand rail termination that swoops down and curls back up slightly.
  • Goose-neck: The vertical handrail that joins a sloped handrail to a higher handrail on the balcony or landing is a goose-neck.
  • Rosette: Where the handrail ends in the wall and a half-newel is not used, it may be trimmed by a rosette.
  • Easing: Wall handrails are mounted directly onto the wall with wall brackets. At the bottom of the stairs such railings flare to a horizontal railing and this horizontal portion is called a "starting easing". At the top of the stairs, the horizontal portion of the railing is called a "over easing". Over easing are required for commercial applications as well as ADA access.
  • Baluster: A term for the vertical posts that hold up the handrail. Sometimes simply called guards or spindles. Treads often require three or more balusters. Building codes require that the spacing between balusters be no more than four inches.
  • Newel Post:  A large baluster or post used to anchor the handrail. Since it is a structural element, it often extends below the floor and sub-floor or tread to the floor joists or are bolted through the floor.  joist.
  • Finial: A decorative cap to the top of a newel post, particularly at the end of the balustrade.
  • Baserail or Shoerail : For systems where the baluster does not start at the treads, they go to a baserail. This allows for identical balusters.

Other terminology

  • Balcony:  For stairs with an open concept upper floor or landing, the upper floor is functionally a balcony. For a straight flight of stairs, the balcony may be long enough to require multiple newels to support the length of railing. In modern homes, it is common to have hardwood floors on the first floor and carpet on the second. The homeowner should consider using hardwood nosing in place of carpet. Should the carpet be subsequently replaced with hardwood, the balcony balustrade may have to be removed to add the nosing.
  • Landing or Platform: A landing is the area of a floor near the top or bottom step of a stair. An intermediate landing is a small platform that is built as part of the stair between main floor levels and is typically used to allow stairs to change directions, or to allow the user a rest. A half landing is where a 180° change in direction is made, and a quarter landing is where a 90° change in direction is made (on an intermediate landing) As intermediate landings consume floor space they can be expensive to build. However, changing the direction of the stairs allows stairs to fit where they would not otherwise, or provides privacy to the upper level as visitors downstairs cannot simply look up the stairs to the upper level due to the change in direction.
  • Measurements: The measurements of a stair, in particular the rise height and going or run of the steps, should remain the same along the stairs.