CodeMandatory
A single stair flight has at most 12 ft 7 in vertical rise
2025 RCNYS §R318.7.3 Stairway vertical riseDescription
A flight of stairs may not rise more than 12 ft 7 in between floor levels or landings. Longer vertical rises require an intermediate landing.
Why this exists
12'7" is the IRC-base maximum and accommodates a standard 10-ft floor-to-floor with comfortable margin. Tall ceilings (12 ft floor-to-floor for over-garage upper levels, for instance) require a landing — architects should plan the landing position into the schematic, not bolt it on after.
Measurements
| Property | Operator | Value | Unit | Note |
|---|---|---|---|---|
maxRise | max | 151 | in (12'7") | Maximum rise per flight without landing |
Categories
Life safetyCirculation
Applies to
- Jurisdiction: New York State
Source
NY Dept of State / ICCno manifest entry
2025 Residential Code of New York State (2025)
Section: R318.7.3 Stairway vertical rise
Published 2025-07-01 · last verified 2026-05-15
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.