ADU · Columbia County
Can you build an ADU in Hudson, NY?
City of Hudson has 12 districts. All districts allow ADUs with occupancy restrictions. Check your address to confirm the district that applies to your parcel:
What the Hudson code says
An accessory dwelling unit is permitted in every district, but only as accessory to a one-family dwelling. The owner must live on the parcel when applying and keep a primary domicile in the house or ADU for at least 12 continuous months after its certificate of occupancy.
Conditions the code attaches:
- One ADU per building lot, at least 350 sq ft and no larger than the gross floor area of the principal dwelling.
- The house and ADU must be commonly owned and stay on the same tax lot, so the unit cannot be split off and sold.
- The ADU must sit in a rear or side yard, never the front yard, on a permanent foundation, with no driveway access separate from the one serving the house.
- An ADU is permitted on a preexisting lot that is nonconforming in lot size, but must meet the setback, height and parking requirements for a one-family dwelling in its district.
- An existing nonconforming accessory structure, such as a garage, can become an ADU without curing its nonconformity if its footprint is not enlarged and the other ADU rules are met.
- A building permit and certificate of occupancy are required, not a special use permit or site plan review, and water and sewage must meet Columbia County Department of Health standards.
What the Hudson 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 Residential | 0.11 ac | 20 / 10 / 30 ft | 35 ft | Occupancy restricted |
| One- or Two-Family Residential | 0.09 ac | 15 / 7.5 / 30 ft | 35 ft | Occupancy restricted |
| Multiple Dwelling Residential | 0.18 ac | 10 / 10 / 30 ft | 35 ft | Occupancy restricted |
| Multiple Dwelling (High-Density) | 0.14 ac | 10 / 10 / 30 ft | 45 ft | Occupancy restricted |
| Institutional-Residential Conservation | 0.23 ac | 20 / 15 / 30 ft | 35 ft | Occupancy restricted |
| Riverfront Gateway | 0.14 ac | 10 / 10 / 30 ft | 45 ft | Occupancy restricted |
| Core Riverfront | 0.14 ac | 10 / 10 / 20 ft | 35 ft | Occupancy restricted |
| Recreational Conservation | 0.28 ac | 20 / 15 / 30 ft | 35 ft | Occupancy restricted |
| City Core Commercial | — | — | 45 ft | Occupancy restricted |
| Commerce District | 0.11 ac | - / - / 20 ft | 35 ft | Occupancy restricted |
| General Commercial | 0.23 ac | - / 10 / 20 ft | 35 ft | Occupancy restricted |
| Industrial | — | - / 10 / 10 ft | 45 ft | Occupancy restricted |
One-Family Residential - The Planning Board may approve a front yard that conforms with the prevailing building setback on the property's street, instead of the figure shown.
- The minimum lot area is for one family on one lot, not a figure per dwelling unit.
- Density and the number of lots a parcel may be subdivided into are calculated on net parcel size under § 325-18C.
- Article V sets alternative dimensions for conservation development and incentive zoning.
One- or Two-Family Residential - The Planning Board may approve a front yard that conforms with the prevailing building setback on the property's street, instead of the figure shown.
- The figures shown apply to one- or two-family dwellings.
- Density and the number of lots a parcel may be subdivided into are calculated on net parcel size under § 325-18C.
- Article V sets alternative dimensions for conservation development and incentive zoning.
Multiple Dwelling Residential - The figures shown are for multiple dwellings. Each dwelling unit needs 400 sq ft of usable open space, and the maximum building length is 160 ft.
- A one- or two-family dwelling takes a different column: 0.0918 acres on 40 ft of width, with a 15 ft front, 7.5 ft side and 30 ft rear yard, 35% coverage and 2,400 sq ft per dwelling unit.
- An attached dwelling needs 20 ft of lot width per unit, 35 ft for an end unit including a 15 ft side yard, and 2,000 sq ft per dwelling unit with no total lot area stated.
- New office buildings, or buildings combining office and residential use, need 10,000 sq ft on a 100 ft lot, with a 10 ft front, 15 ft side and 30 ft rear yard and 30% coverage.
- The Planning Board may approve a front yard that conforms with the prevailing building setback on the property's street, instead of the figure shown.
- Density and lot count are calculated on net parcel size under § 325-18C, and Article V sets alternative dimensions for conservation development and incentive zoning.
Multiple Dwelling (High-Density) - The side yard is ten feet or half the building height, whichever is greater. Each dwelling unit needs 300 sq ft of usable open space, and the maximum building length is 160 ft.
- A one- or two-family dwelling takes a different column: 0.0918 acres on 40 ft of width, with a 15 ft front, 7.5 ft side and 30 ft rear yard, 35 ft of height, 35% coverage and 2,400 sq ft per unit.
- An attached dwelling needs 20 ft of lot width per unit, 2,000 sq ft per dwelling unit with no total lot area stated, and 400 sq ft of usable open space per unit.
- The figures shown are for multiple dwellings; one- or two-family dwellings and attached dwellings have separate standards.
- The Planning Board may approve a front yard that conforms with the prevailing building setback on the property's street, instead of the figure shown.
- Density and the number of lots a parcel may be subdivided into are calculated on net parcel size under § 325-18C.
- Article V sets alternative dimensions for conservation development and incentive zoning.
Institutional-Residential Conservation, Recreational Conservation - Each dwelling unit needs 500 sq ft of usable open space, and the Planning Board may approve a front yard that conforms with the prevailing building setback on the property's street.
- Density and the number of lots a parcel may be subdivided into are calculated on net parcel size under § 325-18C.
- Article V sets alternative dimensions for conservation development and incentive zoning.
Riverfront Gateway - The side yard is ten feet or half the building height, whichever is greater. Each dwelling unit needs 300 sq ft of usable open space, and the maximum building length is 160 ft.
- The Planning Board may approve a front yard that conforms with the prevailing building setback on the property's street, instead of the figure shown.
- Density and the number of lots a parcel may be subdivided into are calculated on net parcel size under § 325-18C.
- Article V sets alternative dimensions for conservation development and incentive zoning.
Core Riverfront - Each dwelling unit needs 400 sq ft of usable open space, and the Planning Board may approve a front yard that conforms with the prevailing building setback on the property's street.
- Density and the number of lots a parcel may be subdivided into are calculated on net parcel size under § 325-18C.
- Article V sets alternative dimensions for conservation development and incentive zoning.
City Core Commercial - No side yard is required, but one that is provided must be at least ten feet. Within 25 ft of a residence district boundary the side yard becomes 10 ft and the rear yard 30 ft.
- Height is also limited to four stories.
- Density and the number of lots a parcel may be subdivided into are calculated on net parcel size under § 325-18C.
- Article V sets alternative dimensions for conservation development and incentive zoning.
Commerce District - No side yard is required, but one that is provided must be at least ten feet. Within 25 ft of a residence district boundary the side yard becomes 10 ft and the rear yard 30 ft.
- Density and the number of lots a parcel may be subdivided into are calculated on net parcel size under § 325-18C.
- Article V sets alternative dimensions for conservation development and incentive zoning.
General Commercial - Within 25 ft of a residence district boundary the side yard becomes 15 ft and the rear yard 30 ft. Area devoted to manufacturing is capped at 10,000 sq ft.
- Density and the number of lots a parcel may be subdivided into are calculated on net parcel size under § 325-18C.
- Article V sets alternative dimensions for conservation development and incentive zoning.
Industrial - Height is limited to two feet for each foot of distance from any property line, up to 45 ft. Within 25 ft of a residence district boundary the side and rear yards both become 40 ft.
- Density and the number of lots a parcel may be subdivided into are calculated on net parcel size under § 325-18C.
- Article V sets alternative dimensions for conservation development and incentive zoning.
ADUs vs. short-term rentals in Hudson
Short-term rentals allowed with local rules for City of Hudson. Hudson requires owner occupancy for a short-term rental, and licenses are capped at 25 city-wide with a maximum of 15 per planning district. A moratorium on new licenses was adopted in June 2024. 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 minimum0.09–0.18 ac — an ADU still has to fit the district's lot and setback envelope.
- UtilityCentral Hudson territory.
- Zoning codeecode360.com/5082256
- Building dept(518) 828-3133
ADU FAQ — Hudson, NY
Are ADUs allowed in Hudson, NY?
City of Hudson has 12 districts. All districts allow ADUs with occupancy restrictions. Check your address with the free ADU checker, or confirm with the building department at (518) 828-3133.
Do I need a special permit for an ADU in Hudson?
No district in City of Hudson requires a special-use permit for an ADU - 12 districts allow ADUs with occupancy restrictions. Site-plan review or a building permit may still apply.
Can I use an ADU as a short-term rental in Hudson?
Short-term rentals allowed with local rules for City of Hudson. 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 Hudson
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 Hudson, priced by size.
How we know this
- Districts confirmed
- 12 of 12 — 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 Hudson: Full zoning for new construction · ADU build cost · House build cost · ADU rules across Columbia County · All Columbia County towns
ADU information for City of Hudson is compiled from the municipal code (last reviewed 2026-06-02) 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) 828-3133 before relying on any answer. Source: the Offsite / Aldo zoning dataset.