Smoke alarms must be in each sleeping room, outside each sleeping area, on each story, away from baths and cooking
2025 RCNYS §R310.3 Smoke alarm location requirementsDescription
Required smoke alarm locations in NY: (1) inside each sleeping room; (2) outside each separate sleeping area, in the immediate vicinity of the bedrooms; (3) on every additional story including basements + habitable attics; (4) at least 3 ft horizontally from any bathroom containing a tub or shower (where this doesn't prevent required placement); (5) in hallways AND in rooms open to the hallway when the open-room ceiling exceeds the hallway by 24 in or more; (6) within sleeping-loft rooms; (7) in shared common spaces of buildings with 3+ dwelling units. On any level over 1000 sqft, the ceiling must have an alarm within 30 ft travel distance from every point (or one alarm per 500 sqft).
Why this exists
The 30-ft / 500-sqft density rule is unique to NY and changes coverage for vaulted-ceiling great rooms. The 3-ft horizontal stand-off from bathrooms minimizes false alarms from shower steam. Architects should locate alarms on the plan during schematic; placing them after rough-in is expensive.
Measurements
| Property | Operator | Value | Unit | Note |
|---|---|---|---|---|
bathStandoff | min | 3 | ft | Stand-off from bath with tub/shower |
densityArea | max | 500 | sqft per alarm | Floor area per smoke alarm on levels >1000 sqft |
densityTravel | max | 30 | ft | Travel distance from any ceiling point to a smoke alarm on levels >1000 sqft |
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.