stair – a series of steps, each elevated a measured distance, leading from one level of a...

STAIR – a series of steps, each elevated a measured distance, leading from one level of a structure to another.

“Flight of Stairs” – a continuous series of steps without breaks formed by landings or other constructions

Types of StairsMain Stairs

Straight Run, Platform, and WindingService Stairs

Stairways are usually not built or installed until after interior wall surfaces are complete and finish flooring has been laid.

Stairwell – the rough opening in the floor above to provide headroom for stairs

Stringer – one of the inclined sides of a stair that supports the risers and treads

Riser – the vertical surface between two treads

Tread – the horizontal face of one step

Nosing – the part of the tread that extends over the riser beneath it

Newel – the post that supports the railing

Handrail – an angled piece supported by a wall or railing intended to be grasped by persons

Balusters – vertical members supporting the handrail on open stairs

Platform – a horizontal area placed between to flights of stairs

Landing – the floor at the top or bottom of each story where a flight of stairs begins or ends

Winders – Wedge-shaped treads installed where stairs turn

Unit Run – the width of a tread minus the nosing

Unit Rise – the height or a riser; vertical distance between two treads

Total Run – the sum of all unit runs

Total Rise – the sum of all unit rises

Headroom – the vertical distance from a step to a ceiling above

The rough opening for the stairwell must be carefully laid out and constructed

Trimmers and headers should be doubled for support

1) Measure total rise (from landing point)2) Decide on number of risers based on 7” to 7

½” risers (unless special circumstances prevent this)

3) Divide total rise by # of risers for riser height4) Subtract # of risers by 1 for # of treads5) Set stair jacks on framing square and trace

onto stringer6) Add and subtract as needed for top and

bottom to adjust for actual floor heights

9’ 2”

9’ 2” = How many inches total rise?110”What is the standard height of a step?7” to 7 ½”Divide total rise by standard riser height110” / 7” = 15.71110” / 7 ½” = 14.6So… 15 risers and 14 steps110” / 15 = 7.3” = single riser heightAnd standard 11” tread w/ nosing

15 Risers14 steps7.3” riser11” step