- Asked 2/32
- 2071 Magh · 8 marks
- 2070 Magh
Elements and types of stair
Short answer
Essential stair elements include tread, riser, nosing, flight, landing, going, rise, waist slab/stringer, soffit, handrail, baluster, newel post, headroom, winder, and pitch line. Types: straight, quarter-turn, dog-legged, open-well, half-turn, three-quarter turn, bifurcated, geometrical, and spiral.
Describe the essential elements of stair. Illustrate the types of stair with sketches.
A stair is a set of steps (a series of risers and treads) that connects floors at different levels, giving access from one storey to another, usually with landings and a balustrade.
Essential elements of a stair
A stair has the following essential elements:
- Step: one riser plus one tread; steps are the basic unit.
- Tread and riser: the tread is the horizontal surface (250-300 mm), the riser the vertical face (150-175 mm).
- Nosing: the rounded projecting edge of the tread (about 25 mm).
- Flight: an unbroken series of steps between landings (3 to 12 steps).
- Landing: a level platform at the ends of a flight or between flights; quarter-space or half-space.
- Going and rise: the horizontal and vertical measurements of a step or flight.
- Waist slab / stringer: the inclined slab or beam which supports the steps.
- Soffit: the underside of the flight.
- Handrail, baluster and newel post: the balustrade that protects the open sides; the handrail is about 0.9 m high.
- Headroom: the clear height above the steps (minimum about 2.0-2.2 m).
- Winder: a tapered step used to turn the stair in a restricted space.
- Pitch line: an imaginary line joining the nosings; its angle with the horizontal is the pitch.
handrail
/| baluster
newel /_|__
| | nosing
riser |____|__ tread
______|
going <--->
Types of stair (with sketches)
| Type | Description |
|---|---|
| Straight (single flight) | One continuous flight between two floors, no turn |
| Quarter-turn | Direction changes by 90 degrees at a quarter-space landing |
| Dog-legged | Two flights in opposite directions with a half-space landing and no well between the flights |
| Open-newel / open-well | Two or more flights with a clear well between them |
| Half-turn (two-flight) | Turn of 180 degrees, either dog-legged or open-well |
| Three-quarter turn | Three flights turning through 270 degrees around a well |
| Bifurcated (branching) | One wide flight splits into two narrower flights at a landing |
| Geometrical | Curved (circular or elliptical) flights round an open well, without newel posts; continuous handrail |
| Spiral / circular (helical) | Winder steps radiating round a central post or on a circular plan; saves space |
Straight Quarter turn Dog-legged Open well
| | | | |_____ |>>>>>| |>>>>>|
| | | | | |<<<<<| | |
| | | |__| |_____| |<<<<|
(well)
Spiral (central post) Bifurcated
___ _|_
/ o \ | |
\___/ \ /
✓ Answer checked by Claude Opus 5.5 (high effort)
Related questions
- Essential requirements and types of stair by shape · Building Technology, chapter 5
- Stair elements, ladders, lifts, elevators and ramps · Building Technology, chapter 5
- Vertical circulation elements; RCC dog-legged stair · Building Technology, chapter 5
- RCC stair for 6.0 m by 4.2 m lobby · Building Technology, chapter 5
- Stair design, 1.8 m by 3.9 m · Building Technology, chapter 5
- Dog-legged stair, 4.5 m by 3.0 m lobby · Building Technology, chapter 5
- Contract and its essential elements · Engineering Professional Practice, chapter 4 · asked 2×
- Contract, essential elements and importance · Construction Management, chapter 5
- Bridge site factors and components with sketches · Transportation Engineering II, chapter 5
- Elements resisting lateral loads in masonry · Concrete Technology and Masonry Structure, chapter 9 · asked 6×