ADU · Dutchess County
Can you build an ADU in Union Vale, NY?
Town of Union Vale has 9 districts. 7 districts allow ADUs with a special-use permit, 2 do not. Check your address to confirm the district that applies to your parcel:
What the Union Vale 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 |
|---|---|---|---|---|
| Rural Development 10 District | 10 ac | 100 / 75 / 100 ft | 35 ft | Special permit |
| Residential Agricultural 5 District | 5 ac | 100 / 50 / 100 ft | 35 ft | Special permit |
| Residential Agricultural 3 District | 3 ac | 75 / 35 / 50 ft | 35 ft | Special permit |
| Residential 1.5 District | 1.5 ac | 50 / 35 / 40 ft | 35 ft | Special permit |
| Residential 1 District | 1 ac | 35 / 35 / 35 ft | 35 ft | Special permit |
| Hamlet District | 1.5 ac | 40 / 25 / 40 ft | 35 ft | Special permit |
| Neighborhood Commercial District | 1 ac | 40 / 25 / 40 ft | 35 ft | Special permit |
| Town Center District | — | 20 / 25 / 80 ft | 35 ft | No |
| Airport District | 2.5 ac | 100 / 50 / 50 ft | 35 ft | No |
Rural Development 10 District — Lot frontage and lot width at the building line are both 375 ft. Parking areas and access driveways have a complete second set of setbacks, separate from the building setbacks above: 75 ft front, 50 ft side, 50 ft rear. Parking is barred from any front yard setback and must go to the rear or side of the principal building, with landscaping and screening under § 210-25B (Note 4). A minimum of 85% of the lot must be left as open space, which is a separate test from the coverage cap. These standards apply to permitted uses; Article VI may set extraordinary standards for special permit uses (Note 1). They are not controlling on municipal uses on municipal property (Note 2). Coverage is BUILDING coverage — the composite footprint of all principal and accessory structures, excluding uncovered porches, terraces and steps.
Residential Agricultural 5 District — Lot frontage and lot width at the building line are both 275 ft. Parking areas and access driveways have a complete second set of setbacks, separate from the building setbacks above: 60 ft front, 25 ft side, 40 ft rear. Parking is barred from any front yard setback and must go to the rear or side of the principal building, with landscaping and screening under § 210-25B (Note 4). A minimum of 80% of the lot must be left as open space, which is a separate test from the coverage cap. These standards apply to permitted uses; Article VI may set extraordinary standards for special permit uses (Note 1). They are not controlling on municipal uses on municipal property (Note 2). Coverage is BUILDING coverage — the composite footprint of all principal and accessory structures, excluding uncovered porches, terraces and steps.
Residential Agricultural 3 District — Lot frontage and lot width at the building line are both 225 ft. Parking areas and access driveways have a complete second set of setbacks, separate from the building setbacks above: 45 ft front, 20 ft side, 25 ft rear. Parking is barred from any front yard setback and must go to the rear or side of the principal building, with landscaping and screening under § 210-25B (Note 4). A minimum of 75% of the lot must be left as open space, which is a separate test from the coverage cap. These standards apply to permitted uses; Article VI may set extraordinary standards for special permit uses (Note 1). They are not controlling on municipal uses on municipal property (Note 2). Coverage is BUILDING coverage — the composite footprint of all principal and accessory structures, excluding uncovered porches, terraces and steps.
Residential 1.5 District — Lot frontage and lot width at the building line are both 175 ft. Parking areas and access driveways have a complete second set of setbacks, separate from the building setbacks above: 30 ft front, 20 ft side, 20 ft rear. Parking is barred from any front yard setback and must go to the rear or side of the principal building, with landscaping and screening under § 210-25B (Note 4). A minimum of 70% of the lot must be left as open space, which is a separate test from the coverage cap. These standards apply to permitted uses; Article VI may set extraordinary standards for special permit uses (Note 1). They are not controlling on municipal uses on municipal property (Note 2). Coverage is BUILDING coverage — the composite footprint of all principal and accessory structures, excluding uncovered porches, terraces and steps.
Residential 1 District — Lot frontage and lot width at the building line are both 150 ft. Parking areas and access driveways have a complete second set of setbacks, separate from the building setbacks above: 25 ft front, 20 ft side, 15 ft rear. Parking is barred from any front yard setback and must go to the rear or side of the principal building, with landscaping and screening under § 210-25B (Note 4). A minimum of 65% of the lot must be left as open space, which is a separate test from the coverage cap. These standards apply to permitted uses; Article VI may set extraordinary standards for special permit uses (Note 1). They are not controlling on municipal uses on municipal property (Note 2). Coverage is BUILDING coverage — the composite footprint of all principal and accessory structures, excluding uncovered porches, terraces and steps.
Hamlet District — Lot frontage and lot width at the building line are DIFFERENT: 100 ft of frontage but 150 ft of width at the building line, so a lot that fronts the road adequately can still be too narrow where the house goes. Parking areas and access driveways have a complete second set of setbacks, separate from the building setbacks above: 25 ft front, 15 ft side, 15 ft rear. Parking is barred from any front yard setback and must go to the rear or side of the principal building, with landscaping and screening under § 210-25B (Note 4). A minimum of 50% of the lot must be left as open space, which is a separate test from the coverage cap. These standards apply to permitted uses; Article VI may set extraordinary standards for special permit uses (Note 1). They are not controlling on municipal uses on municipal property (Note 2). Coverage is BUILDING coverage — the composite footprint of all principal and accessory structures, excluding uncovered porches, terraces and steps.
Neighborhood Commercial District — Lot frontage and lot width at the building line are DIFFERENT: 100 ft of frontage but 150 ft of width at the building line, so a lot that fronts the road adequately can still be too narrow where the house goes. Parking areas and access driveways have a complete second set of setbacks, separate from the building setbacks above: 30 ft front, 15 ft side, 30 ft rear. Parking is barred from any front yard setback and must go to the rear or side of the principal building, with landscaping and screening under § 210-25B (Note 4). A minimum of 40% of the lot must be left as open space, which is a separate test from the coverage cap. These standards apply to permitted uses; Article VI may set extraordinary standards for special permit uses (Note 1). They are not controlling on municipal uses on municipal property (Note 2). Coverage is BUILDING coverage — the composite footprint of all principal and accessory structures, excluding uncovered porches, terraces and steps.
Town Center District — TC publishes NO minimum lot area for a residential lot — the schedule sends you to Note A, which states there is none, and sets the residential density instead at one dwelling unit per half acre before any approved density bonus. A COMMERCIAL lot in TC does have a minimum, of two acres, and a commercial building footprint is capped at 2,500 sq ft, raised to 4,000 sq ft for food and grocery store uses (Note 7). The front setback is a RANGE, not a minimum: 20 ft minimum and 35 ft MAXIMUM, so a building may not be set further back than 35 ft. The 25 ft side yard, and the 20 ft parking side setback, may be cut to ZERO for zero-lot-line development authorised by special use permit where emergency vehicle access is adequate (Note 3) — the trigger is that kind of development rather than the permit alone, so it is stated here rather than as a separate set of standards that any application reaching the Planning Board would qualify for. Residential development fronting Route 55 must devote at least 15% of total building square footage to commercial uses, and the last 25% of dwelling units get no certificate of occupancy until that commercial component is complete (Note 5). Commercial, multifamily, townhouse and mixed-use development must also meet the TC Design Standards at § 210 Attachment 3 (Note 6). Lot frontage and lot width at the building line are both 75 ft. Parking areas and access driveways have a complete second set of setbacks, separate from the building setbacks above: 20 ft front, 20 ft side, 30 ft rear. Parking is barred from any front yard setback and must go to the rear or side of the principal building, with landscaping and screening under § 210-25B (Note 4). A minimum of 50% of the lot must be left as open space, which is a separate test from the coverage cap. These standards apply to permitted uses; Article VI may set extraordinary standards for special permit uses (Note 1). They are not controlling on municipal uses on municipal property (Note 2). Coverage is BUILDING coverage — the composite footprint of all principal and accessory structures, excluding uncovered porches, terraces and steps.
Airport District — Lot frontage and lot width at the building line are DIFFERENT: 100 ft of frontage but 200 ft of width at the building line, so a lot that fronts the road adequately can still be too narrow where the house goes. Parking areas and access driveways have a complete second set of setbacks, separate from the building setbacks above: 35 ft front, 15 ft side, 20 ft rear. Parking is barred from any front yard setback and must go to the rear or side of the principal building, with landscaping and screening under § 210-25B (Note 4). A minimum of 35% of the lot must be left as open space, which is a separate test from the coverage cap. These standards apply to permitted uses; Article VI may set extraordinary standards for special permit uses (Note 1). They are not controlling on municipal uses on municipal property (Note 2). Coverage is BUILDING coverage — the composite footprint of all principal and accessory structures, excluding uncovered porches, terraces and steps.
ADUs vs. short-term rentals in Union Vale
Short-term rentals allowed with local rules for Town of Union Vale. Short-term rental is a defined and regulated use. § 210-85A of Zoning Chapter 210 defines SHORT TERM RENTAL as 'an accessory use or supplementary business in a dwelling unit' letting it for less than 30 days, and ACCESSORY USE is separately defined as customarily incidental and subordinate to the principal use on the same lot. New York State's 2025 short-term rental registry (Ch. 99 of the Laws of 2025) separately requires every host statewide to register the unit regardless of local law. Confirm with Town of Union Vale at (845) 724-5600 before listing. 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 minimum1–10 ac — an ADU still has to fit the district's lot and setback envelope.
- UtilityCentral Hudson territory.
- Zoning codeecode360.com/7977116
- Building dept(845) 724-5600
- Last reviewed2026-08-16
ADU FAQ — Union Vale, NY
Are ADUs allowed in Union Vale, NY?
Town of Union Vale has 9 districts. 7 districts allow ADUs with a special-use permit, 2 do not. Check your address with the free ADU checker, or confirm with the building department at (845) 724-5600.
Do I need a special permit for an ADU in Union Vale?
It depends on the district: 7 of 9 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 Union Vale?
Short-term rentals allowed with local rules for Town of Union Vale. 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 Union Vale
Permission is one question and budget is another. An 800 sq ft accessory unit here runs roughly $210k–275k 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 Union Vale, priced by size.
More on Union Vale: Full zoning for new construction · ADU build cost · House build cost · All Dutchess County towns
ADU information for Town of Union Vale is compiled from the municipal code (last reviewed 2026-08-16) 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) 724-5600 before relying on any answer. Source: Offsite / Aldo zoning dataset, municipalData.js.