Stair flight
A stair flight is a continuous run of steps between floors or landings, capped by the NCC at 18 risers (minimum 2); riser and going uniformity rules apply across it.
Ask Chalkline about this →A stair flight is a continuous run of steps between floors or landings, capped by the NCC at 18 risers (and a minimum of 2) before a landing is required. It is the unit the riser and going uniformity rules apply across.
A flight is an uninterrupted series of steps. The NCC limits it two ways:
- Maximum 18 risers before a landing must break the run. A landing limits how far someone can fall and gives a rest or turn point.
- Minimum 2 risers in a flight. A single isolated step is a trip hazard and is not permitted as a “flight.”
The riser-height and going uniformity tolerance applies within a flight: every riser in a flight must be within the small allowed variation (about 5 mm) of the others, and likewise every going. A landing starts a new flight, so the uniformity is measured flight by flight.
For a builder the practical move is to plan the flights and landings before cutting a stringer: take the total floor-to-floor rise, divide it into flights of no more than 18 risers, and put landings where the geometry needs them. Keep every riser in a flight uniform, the most common stair defect is a first or last riser out of step because the finished floor levels at top and bottom were not accounted for in the set-out. And never leave a single-riser step.
Also known as: Flight of stairs, stair run.
Category: Stairs / Geometry.
Related
See also
References
- Stair geometry (Chalkline) (verified 2026-06-01)
Last updated: 2026-06-01. Verified: 2026-06-01. Quarterly review for currency.