Accessible ramp requirements in California
CBC 11B-405 next to ADA 405: slopes, widths, landings, handrails and edge protection, with a field checklist.
A ramp is any walking surface steeper than 1:20 (5%). It is the element where California and the 2010 ADA differ the most: CBC 11B requires wider runs, longer bottom landings and has no allowance for steeper existing ramps.
CBC 11B-405 vs ADA 405
| Item | CBC 11B (California) | 2010 ADA |
|---|---|---|
| Running slope | 1:12 (8.33%) max, no exception for existing sites · 11B-405.2 | 1:12 max; steeper allowed for short existing ramps · 405.2 |
| Cross slope | 1:48 (2.08%) max · 11B-405.3 | 1:48 max · 405.3 |
| Rise per run | 30 in max · 11B-405.6 | 30 in max · 405.6 |
| Clear width | 48 in min between handrails (36 in for some small residential ramps) · 11B-405.5 | 36 in min · 405.5 |
| Top landing | 60 in long min, 60 in wide min · 11B-405.7.2.1, 11B-405.7.3 | 60 in long, as wide as the ramp · 405.7 |
| Bottom landing | 72 in long min · 11B-405.7.3.1 | 60 in long min · 405.7.3 |
| Change of direction | 60 × 72 in min landing · 11B-405.7.4 | 60 × 60 in min · 405.7.4 |
| Handrails | Both sides, per 11B-505; required unless the run is a curb ramp or a short run at a door landing · 11B-405.8 | Both sides where rise exceeds 6 in · 405.8 |
| Edge protection | Both sides of runs and landings; curb or barrier that stops a 4 in sphere · 11B-405.9 | Extended surface or curb/barrier · 405.9 |
Field checklist
- Running slope measured with a 2-ft smart level at several points along each run, not one average from end to end.
- Cross slope at the same points.
- Total rise of each run (30 in max) and the length of each landing in the direction of travel.
- Clear width measured between the handrails, not between the walls.
- Handrails: 34 to 38 in to the top of the gripping surface, continuous, 1¼ to 2 in diameter, 1½ in clear of the wall, 12 in horizontal extensions at top and bottom.
- Edge protection on both sides, and no drop-off at the landing edges.
- Door swing at the top landing does not reduce the landing below its required size.
- Surface firm, stable and slip resistant, with no cracks or lips over ¼ in.
Writing ramp findings
Write the steepest measured slope and where it was taken, not the average: a ramp with a 1:12 average can still have a 10% section. Slope and landing problems usually mean rebuilding the ramp, so give them a clear priority. Handrails and edge protection are often a cheaper, separate correction. See how to write a CASp report.
This guide is general information, not legal advice. Codes and statutes change; always check the current edition of the California Building Code, the 2010 ADA Standards and the Civil Code before you rely on a number.
Write the report in the fieldPARS CASp checks your level and tape readings against CBC 11B and the 2010 ADA side by side, keeps photos with each finding, and builds the CASp report for you. iPhone, iPad and Mac.
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