Accessibility · Ramps

Ramp Running Slope

Maximum running slope for an accessible ramp, expressed as a rise-to-run ratio.

1:12 max

Description

A 1:12 maximum slope (rise:run) is the standard accessible ramp maximum, meaning 1 in of rise for every 12 in of horizontal run. Gentler slopes are preferred wherever space allows, and cross slope (perpendicular to travel) must be much flatter.

Notes

  • Maximum rise for any single ramp run is typically 760 mm (30 in) before a landing is required.

Sources

  • ADA Standards for Accessible Design
  • ICC A117.1

Tags

Values

Maximum running slopeMaximum
1:12 (8.3%)1:12 (8.3%)
Preferred running slopeRecommended
1:16–1:201:16–1:20
Maximum cross slopeMaximum
1:48 (2%)1:48 (2%)

Related dimensions