ADU · Orange County

Can you build an ADU in Harriman, NY?

Village of Harriman has 7 districts. 6 districts allow ADUs with a special-use permit, 1 does not. Check your address to confirm the district that applies to your parcel:

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What the Harriman code says

In R-100, R-50 and R-M, an accessory apartment may be approved entirely within a single-family detached house connected to Orange County sewer district No. 1 or a similar municipally operated sewer district.

Conditions the code attaches:

The house must be the record owner's principal domicile at application and at all times after, shown by the last recorded deed (§ 140-43A(5)).
The house must have been lawfully built and used as a single-family detached dwelling for at least five years before the application (§ 140-43A(4)).
The Planning Board may waive the five years on a showing that the apartment will let the owner care for a relative, or provide care for the owner-occupant.
The apartment must have at least 300 square feet of habitable floor area and no more than 30% of the house's gross floor area or 750 square feet, whichever is less (§ 140-43A(3)).
A proposed unit larger than that makes the building a two-family dwelling.
A preexisting nonconforming building qualifies only if variances are granted for its nonconforming lot size, yard setbacks, coverage, height and other bulk requirements (§ 140-43A(2)).

What the Harriman 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
Residential	0.34 ac	40 / 20 / 40 ft	35 ft	Special permit
Residential	0.12 ac	25 / 8 / 35 ft	35 ft	Special permit
Multifamily Residential	0.12 ac	25 / 8 / 35 ft	35 ft	Special permit
Central Business	0.12 ac	20 / 0 / 0 ft	35 ft	Special permit
General Business	0.34 ac	50 / 15 / 35 ft	35 ft	Special permit
Industrial	0.92 ac	40 / 20 / 20 ft	50 ft	No
Planned Area Development	5 ac	50 / 30 / 50 ft	35 ft	Special permit

Planned Area Development - The figures shown are for single-family dwellings, one dwelling unit to a lot. The yards apply to the outer property lines only and the coverage to the whole tract developed as a planned unit development.

A planned unit development is a special permitted use, and needs at least fifty dwelling units on a tract in one ownership, with central water and sewer (§ 140-40).
Land per unit runs ten thousand square feet for a single-family detached unit, four thousand for a townhouse, five thousand for a two-family and three thousand for a multifamily unit.
Those land-per-unit figures apply after a twenty percent deduction from the tract's gross area.
At least twenty percent of the tract must be common open space, and buildings must stand ten feet back from internal roads.
On that single-family row, a one-bedroom unit needs at least eight hundred square feet of habitable area and a two-bedroom at least twelve hundred.
Crops and orchards, colleges, and the uses allowed as in the I district take their own rows, with lots of five and ten acres on wider frontages.

ADUs vs. short-term rentals in Harriman

No local short-term-rental law on record - which is not the same as permission for Village of Harriman. The Village of Harriman has no local short-term rental law, and that is not the same as permission. Confirm with the Village building department before counting on short-term rental income. 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 minimum0.12–0.34 ac — an ADU still has to fit the district's lot and setback envelope.
UtilityOrange & Rockland territory.
Zoning codeecode360.com/12443678
Building dept(845) 782-6892

ADU FAQ — Harriman, NY

Are ADUs allowed in Harriman, NY?

Village of Harriman has 7 districts. 6 districts allow ADUs with a special-use permit, 1 does not. Check your address with the free ADU checker, or confirm with the building department at (845) 782-6892.

Do I need a special permit for an ADU in Harriman?

It depends on the district: 6 of 7 require a special-use permit, the rest do not. Check the district that applies to your parcel before you design.

Can I use an ADU as a short-term rental in Harriman?

No local short-term-rental law on record - which is not the same as permission for Village of Harriman. 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.

Run the free ADU check for your parcel →

What an ADU costs to build in Harriman

Permission is one question and budget is another. An 800 sq ft accessory unit here runs roughly $205k–270k 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 Harriman, priced by size.

How we know this

Sections analyzed: § 140-42 · § 140-43 · § 140-4
Districts confirmed: 7 of 7 — every mapped district.
Last reviewed: 2026-07-12
Not covered here: Overlay districts, the zoning map, and any conditions attached to an individual parcel. Size limits and owner-occupancy terms sit in the code section above, not in this summary.

More on Harriman: Full zoning for new construction · ADU build cost · House build cost · ADU rules across Orange County · All Orange County towns

ADU information for Village of Harriman is compiled from the municipal code (last reviewed 2026-07-12) 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 (845) 782-6892 before relying on any answer. Source: the Offsite / Aldo zoning dataset.