| Primary value | 1.8 m² |
| Applies to | Bath-only rooms · Shower-only rooms (with washbasin) |
| Exceptions | Minimum width → 1.2 m |
| Measured as | Carpet area within walls. Sanitary fittings (basin, shower tray) count as part of this area. |
| Source | NBC 2016 — Part 4, Clause 5.4.5 ✓ Verified |
1.8 m² is the smallest plan in which an adult can stand, turn, and use a basin + shower without contortions. The 1.2 m minimum width allows the door to swing without hitting fixtures.
Modern bathrooms typically run 2.5–4 m². Master bathrooms in premium housing reach 6+ m².