Ramp Cross Slope, Width, and Edge Protection (2010 ADA Standards 405)
The layout can be right and the ramp still wrong. Cross slope is 1:48 -- about 2% -- flatter than the drainage most sitework targets, so the ramp that sheds water beautifully is the one that fails, after the concrete is down. Clear width is 36 in measured BETWEEN THE HANDRAILS where rails are provided, so a 36 in ramp with rails on both sides is not a 36 in ramp any more and the fix is a wider slab. Where a ramp CHANGES DIRECTION the landing is 60 x 60, which turns a switchback into a wider footprint than anyone drew. And a handrail is not edge protection -- the hazard is at the wheel, not the hand.
Formula and source
cross slope no steeper than 1:48. Clear width 36 in minimum, measured between the handrails where handrails are provided, so the required run width = 36 in + whatever the rails take. Landing clear length 60 in minimum and clear width at least the widest run reaching it; where the ramp changes direction, the landing is 60 in by 60 in minimum. Edge protection is either the surface extended 12 in beyond the inside face of the handrail or a curb or barrier stopping a 4 in sphere within 4 in of the surface.
2010 ADA Standards for Accessible Design, 405.3, 405.5, 405.7.2, 405.7.3, 405.7.4, and 405.9. A US federal standard in the public domain, quoted directly.
Audience
This tile is built for trades and the adjacent professions in the Carpentry and Construction group. The interactive calculator runs entirely in your browser. No account, no fee, no advertising, no tracking.
Related tools
Posture
Rough Logic answers the math question the working professional asks on the job. The site is a calm, fast, ad-free, account-free, ever-free reference. It does not interpret code. It does not replace the licensed professional. It does not store your inputs. The Authority Having Jurisdiction governs all installations and inspections.