North Salem ADU Zoning Guide

Last reviewed 2026-04-27

Max size750 sq ft
Owner occupancyRequired

North Salem permits accessory apartments under §250-68 of Chapter 250 (Article XIII). The main dwelling must contain at least 1,500 sq ft of habitable space, and the accessory apartment itself is capped at the lesser of 750 sq ft or 25% of the main dwelling's habitable space. Approval is by the Board of Appeals via special permit.

Status

Adoption status: Active — accessory apartments are a permitted use by special permit of the Board of Appeals in the R-1 district under Chapter 250 §250-68A
Governing ordinance: Town of North Salem Zoning Code, Chapter 250, §250-68A (Accessory Apartments); supplemental standards in Article XIII
2026 amendment: Local Law #01-2026 (adopted January 27, 2026) amended §250-68A Accessory Apartments as part of a package regulating short-term rentals; the specific changes to the ADU section are not detailed in the Board Agenda but the amendment was adopted
Zoning districts enumerated: R-1 (Medium Density Residential), R-2 (Low Density Residential), R-4 (Rural Density Residential)

Eligibility

Where ADUs are allowed

Zoning districts permitted: R-1 (Medium Density) confirmed via the use table as a Board of Appeals special permit use. R-2 (Low Density) and R-4 (Rural Density) are plausible but require direct verification of each zone’s use table.
Lot type / use restrictions: Single-family detached dwellings only. The main dwelling must contain at least 1,500 sq ft of habitable space to be eligible for an accessory apartment within it (per §250-68).
Minimum lot area required: R-1 = 1 acre minimum; R-2 = 2 acres minimum; R-4 = 4 acres minimum. The accessory apartment itself does not have a separate lot-area minimum beyond the underlying zone.
Limit per property: One ADU per lot.

Types allowed

Attached ADU (interior conversion — in main dwelling): Yes — specifically listed as "Accessory apartment units in main dwellings" in the use table
Detached ADU (garage or accessory building conversion): Yes — specifically listed as "Accessory apartment units in garages or accessory buildings" in the use table (Use Group same as principal use)
Detached ADU (new construction): Not explicitly listed; only conversions of existing main dwellings and garages/accessory buildings are enumerated; confirm with Building Department

Size and placement

Size limits

Minimum sq ft: 300 sq ft
Maximum sq ft: The lesser of 750 sq ft or 25% of the habitable space of the main dwelling, unless the Board of Appeals finds a greater or lesser amount warranted by specific circumstances (per §250-68)

Setbacks

Zone	Minimum Lot Area	Front Yard	Side Yard	Rear Yard
R-1	1 acre	Confirm with code	Confirm with code	Confirm with code
R-2	2 acres	Confirm with code	Confirm with code	Confirm with code
R-4	4 acres	Confirm with code	Confirm with code	Confirm with code

General rule: Accessory structures in the R-1 district must comply with applicable district setback requirements per Chapter 250

Rules for use

Parking

Minimum requirement: 2 off-street parking spaces for single-family dwellings (per R-1 use table); additional ADU-specific parking requirements are specified in Article XIII supplemental standards

Owner occupancy

Required: Yes — owner occupancy is required

Rental use

Short-term rental: Note — the January 2026 local law that amended §250-68A was primarily focused on establishing short-term rental regulations and ensuring ADU provisions are not in conflict; the Town adopted STR regulations as a conditional use in R-4, R-2, R-1, R-1/2, R-1/4, NB, GB, and PO districts. Homeowners with an ADU special permit should confirm with the Building Department whether the primary unit can be rented short-term
Long-term rental: Permitted for the ADU

How to apply in North Salem

Special permit required: Board of Appeals special permit required for all accessory apartments in the R-1 district; same process is expected in R-2 and R-4
Supplemental standards: Article XIII (Conditional Use and Special Permit Standards) contains the specific dimensional, operational, and design standards that the Board of Appeals applies; full Article XIII text not retrieved
Building permit: Required after Board of Appeals approval
Contact: Town of North Salem Building Department, 66 June Road, North Salem, NY 10560

Recent and pending changes

Local Law #01-2026 (adopted January 27, 2026)
Amended §250-68A Accessory Apartments in connection with a new STR regulatory framework for North Salem; the STR regulations permit short-term rentals as a conditional use in residential and business districts with Planning Board Conditional Use Permit and Site Plan Approval
STR conditional use (L.L. #01-2026)
STRs are now conditionally permitted in R-4, R-2, R-1, R-1/2, R-1/4, NB, GB, and PO districts subject to Planning Board approval. The amendment also touched §250-68A (ADUs), suggesting the ADU standards may have been clarified or tightened to prevent overlap

Important details

North Salem is in Westchester County, not Putnam County: Despite being at the Putnam-Westchester border, North Salem is a town of Westchester County. The Putnam County Health Dept. septic/water approval requirement does not apply; Westchester County rules apply instead
Use group "same as principal use": The R-1 use table notes that accessory apartments in garages or accessory buildings are Use Group "same as principal use" — this means garages and accessory buildings converted to ADUs are treated the same as the principal residential use for zoning purposes
Article XIII governs details: All specific supplemental standards (size, setbacks, owner occupancy, parking details) are in Article XIII of Chapter 250; request a copy from the Building Department or review at the Town Hall before starting your project

Frequently asked questions

Can I have more than one ADU on my property in North Salem?

No. North Salem permits one accessory apartment per lot under §250-68.

Where can I put an ADU in North Salem?

Accessory apartments are permitted in R-1 (Medium Density) under §250-68 as a Board of Appeals special permit use. The main dwelling must contain at least 1,500 sq ft of habitable space.

Do I need a special permit to build an ADU in North Salem?

Yes, a special permit is required for construction and maintenance of an accessory apartment per Article XIII Section 250-68. Apply to the Zoning Board of Appeals for approval.

Sources (5)

Last reviewed 2026-04-27. Local rules can change — verify the latest details with the North Salem planning department, or book a free consultation with our team before starting your project. This page is informational and is not legal advice.