Habitable rooms ≥ 70 sqft floor area and ≥ 7 ft in any horizontal dimension (kitchens exempt)
2025 RCNYS §R312.1 / R312.2 Minimum habitable room area + dimensionDescription
Every habitable room must have at least 70 sqft of floor area AND a minimum horizontal dimension of at least 7 feet (no 6×12 bedrooms). Kitchens are exempt from these minimums (since they're sized for fixture clearance, not occupancy). Portions of a sloping-ceiling room with ceiling height under 5 ft, or furred-ceiling room with ceiling height under 7 ft, do not contribute to the required minimum area.
Why this exists
The 70 sqft / 7 ft rule is the foundation residential-design minimum for any habitable space — bedrooms, living rooms, dining rooms. Architects working in tight footprints must check both numbers (a 5×14 room is 70 sqft but fails the 7-ft minimum dimension). The sloping-ceiling carve-out matters in habitable attics + dormer bedrooms.
Measurements
| Property | Operator | Value | Unit | Note |
|---|---|---|---|---|
minArea | min | 70 | sqft | Minimum habitable floor area |
minDimension | min | 7 | ft | Minimum horizontal dimension |
slopingFloorMin | min | 5 | ft | Ceiling height below which floor area doesn't count (sloped ceiling) |
Categories
Applies to
- Jurisdiction: New York State
Source
Solver enforcement
Browsable only — the solver does not currently enforce this directive (no spec-level data to check against). This entry exists so the architect personas can cite it in conversation and the user can read what the rule says.
Related directives
- Garage / dwelling fire separation · IRC R302.6
- Habitable space minimum ceiling height · IRC R305.1
- Egress window net opening dimensions · IRC R310.2
- Stair riser, tread, and headroom · IRC R311.7
- Smoke alarms required throughout dwelling · IRC R314
Last reviewed 2026-05-15.