Stair dimensions and handrail heights in UK homes
In a dwelling the handrail sits 900–1000 mm above the pitch line or landing floor, headroom over the flight is a minimum of 2000 mm, and the going of a tapered tread is measured at the centre of the flight with at least 50 mm at the narrow end. A stair wider than 1000 mm needs a handrail on both sides.
The figures on one page
| Item | Limit | Figure |
|---|---|---|
| Handrail height on a stair or rampPrivate stair, landing or ramp in a dwelling | Range | 900–1000 mm above the pitch line or floor |
| Headroom over a stairStairs and landings within a dwelling | Minimum | 2000 mm, reducing to 1900 mm at the centre of a loft conversion stair and 1800 mm at the side |
| Going of a tapered treadWinder or tapered tread in a private stair | Minimum | Measured at the centre of the flight; at least 50 mm at the narrow end |
| Door swing clearance at stair landingsdoor swings on or near landings do not impede safe passage, particularly verifying the 400mm minimum clearance from the first tread on private stair bottom landings. | Minimum | 400 mm |
| Doors onto a protected stairway in a three-storey houseApplies where any floor level is more than 4.5 m above ground level | Minimum | Fire doors to every habitable room opening onto the stair |
| Handrails for external stepsA handrail is required for external flights of steps when the total rise exceeds 600mm and the individual step going is less than 600mm | exact | 600 mm |
| Handrails for Tapered Treads and WindersFor stairs incorporating tapered treads or winders, any handrail provided on the outside of the turn must offer a safe handhold for the full rise of the stair, particularly if the total rise exceeds 600mm | Maximum | 600 mm |
| Landing length at the top and bottom of a flightLanding at the head or foot of a private stair | Minimum | At least equal to the least width of the flight, kept clear of door swings |
| Private stair rise, going and pitchPrivate stair within a single dwelling | Range | Rise 155–220 mm, going at least 220 mm, maximum pitch 42°, and twice the rise plus the going between 550 mm and 700 mm |
| Stair Handrail Height and ClearanceA handrail is mandatory for flights of stairs where the rise exceeds 600mm | Minimum | 600 mm |
| Stair rise and going relationshipStaircases must be dimensioned such that the relationship between the rise (R) and the going (G) falls within prescribed limits for safety and comfort, typically expressed as 2R + G between 550mm and 700mm | exact | 550 mm |
| Staircase guarding requirementsStaircases and landings require adequate guarding where there is a drop of more than 600mm | exact | 600 mm |
| Tread overlap for open-riser stairsFor stairs with open risers, each tread must overlap the one below by a minimum of 16mm, or 15mm in Scotland, to meet safety requirements and prevent foot entrapment. | Minimum | 16 mm |
What this means on site
Rise and going work as a pair: every step in a flight must have the same rise and the same going, and the mix of the two has to fall within the permitted relationship rather than each simply meeting its own limit.
Loft conversion stairs get a relaxed headroom allowance, and door swings onto a landing must not reduce the usable landing area at the head or foot of a flight.
What actually gets picked up
- Handrail set to the top of the newel rather than measured from the pitch line, putting it outside 900–1000 mm.
- One odd riser at the top or bottom of a flight where the finished floor build-up was not allowed for.
- Headroom pinched by a bulkhead or trimmer at the head of the flight.
- Winder goings measured at the wall string instead of the centre line of the flight.
Questions we get asked
- What height should a stair handrail be in the UK?
- Between 900 mm and 1000 mm measured vertically from the pitch line of the flight, or from the floor on a landing.
- What height should a banister rail be?
- The same 900–1000 mm range applies to the handrail on a balustrade to a flight; landing guarding to a dwelling is 900 mm minimum.
- How is the going of a winder measured?
- At the centre of the flight, and it must never be less than 50 mm at the narrow end of the tread.
Where this is inspected
This is ProPlot's editorial summary of publicly available UK regulation and good practice. It is not building control approval or a warranty determination, and the designer's or manufacturer's tighter figure always takes precedence.