| Primary value | 3.0 m |
| Applies to | One-way basement parking ramps · Single-lane multi-level parking ramps |
| Exceptions | Two-way ramp → 6.0 m |
| Measured as | Clear width between kerbs / wall faces of the ramp — measured horizontally. |
| Source | NBC 2016 — Part 3, Clause 8 ✓ Verified |
Parking ramps serve as the bottleneck between street level and basement parking. 3.0 m one-way is the minimum that lets cars climb without scraping side walls, especially since climbers tend to drift.
Most basement parking uses 3.0 m one-way ramps with separate up and down. Combined two-way ramps (6.0 m) are used in tighter plots where two ramps don't fit.