Dryer exhaust must terminate outside, ≥ 3 ft from any building opening, with backdraft damper, no screen
2025 RCNYS §M1502.3 Dryer exhaust termination 3 ft from openingsDescription
Dryer exhaust ducts must terminate on the outside of the building (not into an attic, crawl space, or soffit). Where the dryer manufacturer's instructions don't specify, the termination must be at least 3 ft in any direction from openings into the building — including openings in vented soffits. The termination requires a backdraft damper. Screens are NOT allowed at the termination (they clog with lint). Termination opening must provide ≥ 12.5 sqin of free area.
Why this exists
Lint discharged into attics is the common defect that causes dryer-fed fires and moisture damage. The 3-ft separation prevents the warm wet exhaust from being immediately drawn back into a soffit vent. Architects should show the dryer termination location + clearances on the elevations.
Measurements
| Property | Operator | Value | Unit | Note |
|---|---|---|---|---|
openingSeparation | min | 3 | ft | Separation from any building opening |
freeArea | min | 12.5 | sqin | Minimum termination free area |
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
- Natural light in habitable rooms · IRC R303.1
- Habitable space minimum ceiling height · IRC R305.1
- Egress window net opening dimensions · IRC R310.2
- Stair riser, tread, and headroom · IRC R311.7
Last reviewed 2026-05-15.