ADU · Westchester County
Can you build an ADU in Larchmont, NY?
Village of Larchmont has 10 districts. All districts prohibit ADUs. Check your address to confirm the district that applies to your parcel:
What the Larchmont code indicates by district
The table below shows how each district treats ADUs, alongside the lot and setback standards that govern a second unit. District boundaries and conditions vary, so treat this as a starting point and confirm the district that applies to your parcel.
| District | Min lot | Setbacks F / S / R | Max height | ADU |
|---|---|---|---|---|
| One-Family Residence | 0.6887 ac | — | 30 ft | No |
| One-Family Residence | 0.2296 ac | — | 30 ft | No |
| One-Family Residence | 0.287 ac | — | 30 ft | No |
| One-Family Residence | 0.3444 ac | — | — | No |
| One-Family Residence | 0.1722 ac | — | 30 ft | No |
| One-Family Residence | 0.1148 ac | — | 30 ft | No |
| Multi-Family Residence | 0.0344 ac | — | 30 ft | No |
| Retail Business | 0.023 ac | — | 25 ft | No |
| Retail Center | 0.023 ac | — | 25 ft | No |
| Waterfront | 0.6887 ac | — | — | No |
ADUs vs. short-term rentals in Larchmont
No local short-term-rental law on record - which is not the same as permission for Village of Larchmont. No local STR ordinance found as of Jun 2026; standard village zoning and building codes apply. Westchester County hotel occupancy tax (3%) applies to short-term stays. These are separate questions from whether you can build an ADU — a unit you're allowed to add isn't automatically one you're allowed to rent nightly, so check both.
Good to know
- Residential lot minimum0.0344–0.6887 ac — an ADU still has to fit the district's lot and setback envelope.
- UtilityCon Edison territory.
- Building dept(914) 834-4349
- Last reviewed2026-06-08
ADU FAQ — Larchmont, NY
Are ADUs allowed in Larchmont, NY?
Village of Larchmont has 10 districts. All districts prohibit ADUs. Check your address with the free ADU checker, or confirm with the building department at (914) 834-4349.
Do I need a special permit for an ADU in Larchmont?
No. No district in Village of Larchmont permits an ADU, so there is no permit to apply for. Codes change, so verify with the building department at (914) 834-4349 before ruling it out.
Can I use an ADU as a short-term rental in Larchmont?
No local short-term-rental law on record - which is not the same as permission for Village of Larchmont. ADU occupancy and short-term-rental rules are separate: an ADU you can build isn't automatically one you can rent nightly. Confirm both before you count on STR income.
What an ADU costs to build in Larchmont
Permission is one question and budget is another. An 800 sq ft accessory unit here runs roughly $235k–310k at a standard finish, and the per-square-foot rate comes in above a full house because the kitchen, bath, panel and heating plant cost the same either way. See the full cost to build an ADU in Larchmont, priced by size.
More on Larchmont: Full zoning for new construction · ADU build cost · House build cost · All Westchester County towns
ADU information for Village of Larchmont is compiled from the municipal code (last reviewed 2026-06-08) and provided for decision-support only — not legal or architectural advice. ADU eligibility, size, owner-occupancy and permit conditions vary by district and often carry exceptions; verify with the building department at (914) 834-4349 before relying on any answer. Source: Offsite / Aldo zoning dataset, municipalData.js.