What height should handrails be for stairs and ramps in the UK?

For stairs, handrails should be between 900mm and 1000mm high, measured vertically from the pitch line (the imaginary line connecting stair nosings). For ramps, the height range is 900mm to 1100mm measured from the ramp surface. BS 8300:2018 specifies these ranges, and they apply to both sides of the stair or ramp.

How long should handrail extensions be?

BS 8300 requires handrails to extend at least 300mm horizontally beyond the top and bottom of each flight. At the top of stairs, the extension continues at the same height horizontally. At the bottom, it extends 300mm horizontally from the bottom nosing. These extensions help users maintain grip as they transition to level ground and provide a tactile warning that the stair or ramp has ended.

What diameter should a handrail be?

BS 8300 specifies a circular cross-section of 40-50mm diameter, with 40-45mm being preferred for the best grip. The rail must be smooth and warm to touch. Non-circular profiles can be used if they provide an equivalent gripping surface, but circular is the standard recommendation. Metal handrails should have a PVC or nylon coating to avoid being cold to touch in winter.

What is the required wall clearance for handrails?

Handrails must have a minimum clearance of 50mm between the rail and any wall or obstruction, with a maximum of 75mm. This allows enough space for a comfortable grip while preventing a child from getting trapped between the rail and wall. Brackets must not obstruct the continuous hand grip and should be positioned on the underside of the rail.

Do I need handrails on both sides of stairs?

Building Regulations Part K requires handrails on at least one side for flights under 1m wide, and on both sides for wider flights. BS 8300 recommends handrails on both sides regardless of width for maximum accessibility. For ramps, Part M and BS 8300 require handrails on both sides for any ramp with a rise exceeding 300mm.

TradeCalculator.co.uk

Handrail Calculator - Part M & BS 8300 Lengths, Heights & Extensions

Calculate handrail lengths, heights and extensions for stairs and ramps per Approved Document M and BS 8300.

Horizontal Length (Going)

Total horizontal going of stair or ramp

Number of Flights

Number of separate flights (between landings)

Total Rise Height

Total vertical rise from bottom to top

TypeStair handrails: 900-1000mm; Ramp handrails: 900-1100mm

How We Calculate This

This calculator determines handrail lengths, bracket quantities, and compliance with BS 8300:2018 and Approved Document M/K for stairs and ramps.

Slope length calculation

The handrail follows the slope of the stair or ramp. The slope length is calculated using Pythagoras: Slope = √(Going² + Rise²). Extensions are added at top and bottom of each flight.

BS 8300 requirements

Height (stairs): 900-1000mm from pitch line
Height (ramps): 900-1100mm from ramp surface
Extensions: Minimum 300mm beyond top and bottom
Diameter: 40-45mm circular (50mm max)
Wall clearance: 50-75mm
Brackets: At 900-1200mm centres, below rail

Material estimate

A 5% waste allowance is added to the total handrail length for cuts, joins, and off-cuts. Bracket quantities are calculated at 1000mm centres with an end bracket at each termination point.