Stair Construction – 3.9.1
The following definitions are used in this part:
Flight means that part of a stair that has a continuous slope created by the nosing line of treads. The length of a flight is limited to restrict the distance a person could fall down a stair.
Quarter landings are considered sufficient to halt a person’s fall and therefore are considered for the purposes of this article not to be part of the flight.
Stair Construction – Terms:
Going – means the horizontal dimension from the front to the back of a tread less any overhang from the next tread above.
Landing – means an area at the top or bottom of a flight or between two flights.
Riser – means the height between consecutive treads.
Spiral Stair – means a stair with a circular plan, winding around a central post with steps that radiate from a common centre or several radii.
Tapered Tread – means a stair tread with a walking area that grows smaller towards one end.
Winders – means treads within a straight flight that are used to change direction of the stair.
Stair Construction – 184.108.40.206
Stairs must be constructed in accordance with the following:
- Each flight must not have more than 18 or less than 2 risers.
- The nominal dimension of goings and risers of a stair must be constant throughout each stair flight except that the going of winders in lieu of a quarter or half landing may vary from going of the straight treads within the same flight provided that the going of all such winders is constant.
- Treads must be of solid construction (not mesh or other perforated materials) if the stairway is more than 10 metres high or connects more than 3 storeys.
- A flight of stairs must not have more than 3 winders in lieu of each quarter landing or 6 winders in lieu of each half landing.
- The riser opening must not allow a 125mm sphere to pass through between the treads.
- Treads must have a slip-resistant finish or suitable non-skid strip near the edge of the nosing’s.