What is the maximum rise for a single ADA ramp run?
A single ADA ramp run may rise a maximum of 30 inches (760 mm) before a level landing is required (2010 ADA §405.6). At the steepest allowed running slope of 1:12, a 30-inch rise means a run of 30 feet, after which the ramp needs a 60-inch landing before the next run continues the climb.
Source: 2010 ADA §405.6 · Verify against your AHJ and the adopted code edition.
There’s no single limit on how tall an accessible ramp can go — but each run (the sloped stretch between landings) is capped. Under 2010 ADA §405.6, a run may rise no more than 30 inches (760 mm) before a landing breaks it up.
Pair that with the maximum running slope of 1:12 (§405.2) and you get the longest a single run can be:
- 30-inch rise ÷ (1 in 12) = 360 inches = 30 feet of ramp run.
- Then a 60-inch landing (§405.7), and the next run repeats.
So a tall ramp becomes a series of ≤30-inch runs separated by landings, often switchbacking to fit the site. Remember the 1:12 slope is the maximum — a gentler slope is easier to use, but it makes each run longer for the same rise. State codes and ICC A117.1 can differ — verify with your AHJ.
Work it out: the ADA ramp calculator takes a total rise and lays it out into compliant runs and landings for you.
Sources
- U.S. Access Board — 2010 ADA Standards — 2010 ADA Standards §405.6, §405.2