| Primary value | 1.1 m² |
| Applies to | Standalone WCs · Powder rooms (half-baths) |
| Exceptions | Minimum width → 0.9 m |
| Measured as | Carpet area within walls. Door swing area should not encroach on the WC clear use zone. |
| Source | NBC 2016 — Part 4, Clause 5.4.5 ✓ Verified |
1.1 m² is the absolute floor for a usable WC compartment — just enough for the pan, knee clearance, and door swing. Below 0.9 m width, the door physically cannot open without hitting the user.
Powder rooms in modern apartments run 1.5–2 m² with an additional washbasin alcove. Below 1.3 m² feels prison-like.