This glossary of staircase related terminology is by no means
exhaustive but does detail the most common and basic terms
used in staircase construction and balustrading installation.

Stair Terminology

Baluster/Spindle – the vertical member, plain or decorative,
that acts as the infill between the handrail and baserail (or
tread if cut string).

Balustrading – the collective name for the complete assembly
of handrails, baserails, newels, spindles and caps.

Bullnose Step – usually at the bottom of the stairs with one or
both ends of the step having a quarter circle design.

Closed String – a string with the face housed/trenched to
accommodate treads and risers so their profile cannot be seen.

Continuous Handrail – using straight lengths of handrail
connected to handrail fittings and ramps, the handrail flows over
the tops of newel turnings creating a continuous run of handrail.

Curtail Step – a decorative shaped step at the bottom of the
stairs usually accommodating the volute and volute newel
turning of the Continuous Handrail System.

Cut or Open String – a string with the upper edge cut away
to the shape of the treads and risers so that their profile can be
seen from the side.

Going – the going of a flight of stairs is the horizontal distance
between the face of the first and last risers. The individual
going of a step is measured from face of riser to face of riser
and for domestic use should be a minimum of 220mm.

Newel – accommodates the strings, handrails and treads/risers
of stairs.

Nosing – the edge of the tread projecting beyond the face of
the riser and the face of a cut string.

OAS – OAS refers to the width of the Staircase = Width Overall Strings.

Pitch – the angle between the pitch line and the horizontal.

Pitch Line – the notional line connecting the nosings of all
treads in a flight of stairs.

Rake – the pitch of the stairs.

Rise – the rise of a flight is the vertical distance between the
floors or landings connected by the flight. The individual rise is
the vertical measurement from top of tread to top of tread.

Riser – the board that forms the face of the step. The
maximum individual rise for domestic flights is 220mm.

Staircase – the entire structure relating to a stair, comprising
steps, treads, risers, strings, balustrading, landings etc.

Stairway/Stairwell – the space/void provided for the stairs.

Stelten – Stelten is the Handrail Fixing we use on our Staircases
Stelten is Short for Steel Tenon

Step – the tread and riser combined.

String Margin – the distance between the top of the string
and the pitch line measured at 90° to the pitch line.

Tread – the top or horizontal surface of a step.

Volute – The detail like a Scroll at the entry of a handrail, sometimes called a Monkey’s Tail, – New Ascending Volute

Wall String – the string of a staircase fixed flush with a wall.

Winders – are radiating steps narrower at one end that are
used to change the direction of a stairs through 90° or 180°.