ADU · Columbia County
Can you build an ADU in Gallatin, NY?
Town of Gallatin has 4 districts. 3 districts allow ADUs with a special-use permit, 1 does not. Check your address to confirm the district that applies to your parcel:
What the Gallatin code says
An accessory dwelling unit is not permitted in H. In the town's other districts it needs a special use permit with site plan approval, and under § 5.2 it must be between 400 and 900 square feet with no more than two bedrooms, with the owner occupying one of the units.
Conditions the code attaches:
- One accessory dwelling unit per lot, and it must be clearly subordinate to the principal use.
- The lot may not be a nonconforming lot below the district's required area or width.
- No accessory dwelling unit may be created on a lot with a two-family or multi-family dwelling, or where two or more dwellings already exist in violation of density.
- A detached unit is allowed under § 5.2.C in an existing gatehouse, garage, barn or similar structure that legally exists when the unit is proposed.
- Water and septic must meet Health Department standards, and the Planning Board may require reserve area for septic replacement.
- The unit needs self-contained cooking, sleeping and sanitary facilities, and any new exterior entrance must be at the side or rear.
What the Gallatin 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 |
|---|---|---|---|---|
| Hamlet | 1 ac | 50 / 25 / 50 ft | 35 ft | No |
| Residential Agricultural (2-Acre) | 2 ac | 75 / 50 / 100 ft | 35 ft | Special permit |
| Low Density Residential (3-Acre) | 3 ac | 75 / 50 / 100 ft | 35 ft | Special permit |
| Residential Agricultural (3-Acre) | 3 ac | 75 / 50 / 100 ft | 35 ft | Special permit |
Hamlet - The lot minimum is measured on net land (§ 4.5.A.3): the FEMA 100-year floodplain, State and Army Corps wetlands, open water and perennial streams, and land of 25% slope or greater are excluded. A parcel that measures three acres on the deed may hold no conforming lot at all.
- Minimum lot frontage is 250 ft, a separate requirement from the lot width shown.
- The land area figure is the amount required per dwelling unit or establishment, not simply a per-lot minimum.
- Two single-family dwellings may share one lot only if it is at least twice the minimum area, each house meets the bulk regulations alone, and each could stand on a conforming subdivided lot (§ 4.2.B).
- A driveway setback of 10 ft applies in H, in addition to the yard figures shown.
- On a through lot, the front yard requirement must be met on both streets (§ 4.3.B.1).
- Disturbance of slopes over 20% must be avoided so far as practicable, and the Planning Board may fix building envelopes and require map notes (§ 4.5.A.4).
Residential Agricultural (2-Acre) - The lot minimum is measured on net land: FEMA 100-year floodplain, state and Army Corps wetlands, open water and perennial streams, and land of 25% slope or greater are excluded (§ 4.5.A.3). A parcel that measures larger on the deed may hold no conforming lot.
- Minimum lot frontage is 250 ft in every district, a separate requirement from the lot width shown.
- Two single-family dwellings may share one lot if it is at least twice the minimum area and each building meets the bulk regulations and could stand on a conforming subdivided lot (§ 4.2.B).
- The land per dwelling unit figure is the area each dwelling unit or establishment requires, not a per-lot minimum.
- A minimum driveway setback of 15 ft applies in this district.
- On a through lot, the front-yard requirement must be met on both streets (§ 4.3.B.1).
- The Planning Board may fix building envelopes and require map notes, and disturbance of slopes over 20% must be avoided so far as practicable (§ 4.5.A.4).
Low Density Residential (3-Acre) - The 3-acre minimum is measured on net land: FEMA 100-year floodplain, state and Army Corps wetlands, open water and perennial streams, and land of 25% slope or greater are excluded (§ 4.5.A.3). A parcel that measures three acres on the deed may hold no conforming lot.
- Two detached single-family houses may share one lot if it is at least twice the minimum area for one and each meets the bulk rules and could stand on a conforming subdivided lot (§ 4.2.B).
- Minimum lot frontage is 250 ft, a separate requirement from the lot width figure shown.
- A minimum driveway setback of 15 ft applies in this district, in addition to the yard setbacks shown.
- On a through lot, the front-yard requirement must be met on both streets (§ 4.3.B.1).
- The Planning Board may fix building envelopes and require map notes, and disturbance of slopes over 20% must be avoided so far as practicable (§ 4.5.A.4).
- The land per dwelling unit figure is the land each dwelling unit or establishment requires, not a per-lot minimum.
Residential Agricultural (3-Acre) - The 3 acre minimum is measured on net land: FEMA 100-year floodplain, State and Army Corps wetlands, land under open water or perennial streams, and land of 25% slope or greater are excluded (§ 4.5.A.3). A parcel measuring 3 acres on the deed may hold no conforming lot.
- The 100 ft wetland buffer is not excluded from the net land calculation.
- Two single-family dwellings may share one lot without subdivision only if the lot is at least twice the minimum area for one (§ 4.2.B).
- Each of those two houses must independently meet the bulk regulations and be able to stand on a conforming subdivided lot.
- Minimum lot frontage is 250 ft, a separate requirement from the lot width shown.
- A minimum driveway setback of 15 ft applies outside H, and on a through lot the front yard requirement must be met on both streets (§ 4.3.B.1).
- The Planning Board may fix building envelopes and require map notes, and disturbance of slopes over 20% must be avoided so far as practicable (§ 4.5.A.4).
ADUs vs. short-term rentals in Gallatin
No local short-term-rental law on record - which is not the same as permission for Town of Gallatin. Gallatin has no confirmed local short term rental rule, so treat renting a home short term as an open question rather than a yes. Confirm with the building department before counting on the use. 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 minimum1–3 ac — an ADU still has to fit the district's lot and setback envelope.
- UtilityNYSEG territory.
- Zoning codegallatinny.gov/wp-content/uploads/2015/11/Gallatin-Zoning-Law.pdf
- Building dept(518) 398-7571
ADU FAQ — Gallatin, NY
Are ADUs allowed in Gallatin, NY?
Town of Gallatin has 4 districts. 3 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 (518) 398-7571.
Do I need a special permit for an ADU in Gallatin?
It depends on the district: 3 of 4 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 Gallatin?
No local short-term-rental law on record - which is not the same as permission for Town of Gallatin. 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 Gallatin
Permission is one question and budget is another. An 800 sq ft accessory unit here runs roughly $195k–260k 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 Gallatin, priced by size.
How we know this
- Districts confirmed
- 4 of 4 — every mapped district.
- Last reviewed
- 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 Gallatin: Full zoning for new construction · ADU build cost · House build cost · ADU rules across Columbia County · All Columbia County towns
ADU information for Town of Gallatin 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 (518) 398-7571 before relying on any answer. Source: the Offsite / Aldo zoning dataset.