What Wheelchair Ramp Gradient Do I Need?

Gradient Requirements (Part M)

• 1:20 (5%): Preferred for all ramps. No going limit
• 1:15 (6.7%): Acceptable for going up to 5m
• 1:12 (8.3%): Maximum steepness, going no more than 2m

Practical Example

For a 150mm step at a front door:

• At 1:12: ramp length = 150 × 12 = 1,800mm (1.8m)
• At 1:15: ramp length = 150 × 15 = 2,250mm (2.25m)
• At 1:20: ramp length = 150 × 20 = 3,000mm (3m)

Key Design Requirements

• Minimum width: 1,000mm between handrails (1,500mm preferred)
• Handrails: Both sides, 900–1,000mm high. Extend 300mm beyond top and bottom
• Level landings: 1,200mm × 1,200mm minimum at top and bottom
• Rest platforms: Every 5m going (at 1:15) or 10m going (at 1:20)
• Kerb/upstand: 100mm minimum on open sides to prevent wheels slipping off
• Surface: Non-slip, contrasting colour nosing at top and bottom

Crossfall

The ramp surface should have a maximum crossfall of 1:40 (2.5%) for drainage. Steeper crossfalls make it difficult for wheelchair users to maintain a straight path.

Important Note

These are general guidelines based on Approved Document M (access to and use of buildings). Always consult Building Control for specific projects, especially for commercial or public buildings where BS 8300 may impose stricter requirements. Individual circumstances may require bespoke solutions.