ADU · Columbia County
Can you build an ADU in Chatham, NY?
Village of Chatham has 6 districts. 3 districts prohibit ADUs, 3 require a special-use permit. Check your address to confirm the district that applies to your parcel:
What the Chatham 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 (1- & 2-family) | 0.17 ac | 30 / 15 / 30 ft | 35 ft | Special permit |
| Suburban Residential | 0.34 ac | 30 / 20 / 50 ft | 35 ft | Special permit |
| Commercial 1 | — | 0 / 0 / 30 ft | 40 ft | No |
| Commercial 2 (Church-Coleman) | 0.17 ac | 30 / 15 / 30 ft | 35 ft | Special permit |
| Commercial 3 (Southern Gateway) | 0.46 ac | 30 / 20 / 50 ft | 35 ft | No |
| Industrial | 0.92 ac | 50 / 30 / 30 ft | 35 ft | No |
Residential (1- & 2-family) — The base row is the 1- AND 2-FAMILY DWELLING case: 7,500 sq ft for the first unit PLUS 2,500 sq ft for the second, which is why the lot figure is the first-unit minimum. A nonresidential use takes 10,000 sq ft on a 75 ft lot. Minimum 1 storey, maximum 2 1/2 and 35 ft. THE RESIDENTIAL COVERAGE LIMIT IS A FORMULA, NOT A PERCENTAGE, and it is the same in EVERY district: maximum lot coverage for residential uses including associated accessory uses is 2,400 sq ft PLUS 25% of the lot area up to 3 acres PLUS 5% of the lot area beyond 3 acres. The percentage recorded above is the NONRESIDENTIAL figure, which is the only one this field can hold. The schedule sets a MINIMUM number of storeys as well as a maximum — a floor on building height, which is unusual and has no field. The Historic Overzone (HO) applies the density regulations of the underlying district, so it adds no figures of its own. See § 110-47 for existing undersized lots and § 110-24 for accessory structures and uses. Minimum 1 storey(s), maximum 2 1/2 and 35 ft. Nonresidential minimum lot width 75 ft.
Suburban Residential — The base row is the 1- AND 2-FAMILY DWELLING case: 15,000 sq ft for the first unit PLUS 5,000 sq ft for the second. A nonresidential use takes 20,000 sq ft on a 100 ft lot. THE RESIDENTIAL COVERAGE LIMIT IS A FORMULA, NOT A PERCENTAGE, and it is the same in EVERY district: maximum lot coverage for residential uses including associated accessory uses is 2,400 sq ft PLUS 25% of the lot area up to 3 acres PLUS 5% of the lot area beyond 3 acres. The percentage recorded above is the NONRESIDENTIAL figure, which is the only one this field can hold. The schedule sets a MINIMUM number of storeys as well as a maximum — a floor on building height, which is unusual and has no field. The Historic Overzone (HO) applies the density regulations of the underlying district, so it adds no figures of its own. See § 110-47 for existing undersized lots and § 110-24 for accessory structures and uses. Minimum 2 storey(s), maximum 2 1/2 and 35 ft. Nonresidential minimum lot width 100 ft.
Commercial 1 — C-1 PUBLISHES ALMOST NO LOT STANDARD: the schedule prints "N.R." — not required — for the residential and nonresidential minimum lot area AND for both lot widths. Its front yard is a RANGE of 0 to 10 ft residential and 0 to 0 ft nonresidential, and no coverage percentage is required. Note 1: the front yard shall be reduced or enlarged to conform to neighbourhood conditions. THE RESIDENTIAL COVERAGE LIMIT IS A FORMULA, NOT A PERCENTAGE, and it is the same in EVERY district: maximum lot coverage for residential uses including associated accessory uses is 2,400 sq ft PLUS 25% of the lot area up to 3 acres PLUS 5% of the lot area beyond 3 acres. The percentage recorded above is the NONRESIDENTIAL figure, which is the only one this field can hold. The schedule sets a MINIMUM number of storeys as well as a maximum — a floor on building height, which is unusual and has no field. The Historic Overzone (HO) applies the density regulations of the underlying district, so it adds no figures of its own. See § 110-47 for existing undersized lots and § 110-24 for accessory structures and uses. Minimum 2 storey(s), maximum 3 and 40 ft.
Commercial 2 (Church-Coleman) — C-2 is the Church-Coleman district. The base row is the residential case: 7,500 sq ft for the first unit PLUS 2,500 for the second. A nonresidential use takes 15,000 sq ft on a 75 ft lot. THE RESIDENTIAL COVERAGE LIMIT IS A FORMULA, NOT A PERCENTAGE, and it is the same in EVERY district: maximum lot coverage for residential uses including associated accessory uses is 2,400 sq ft PLUS 25% of the lot area up to 3 acres PLUS 5% of the lot area beyond 3 acres. The percentage recorded above is the NONRESIDENTIAL figure, which is the only one this field can hold. The schedule sets a MINIMUM number of storeys as well as a maximum — a floor on building height, which is unusual and has no field. The Historic Overzone (HO) applies the density regulations of the underlying district, so it adds no figures of its own. See § 110-47 for existing undersized lots and § 110-24 for accessory structures and uses. Minimum 2 storey(s), maximum 2 1/2 and 35 ft. Nonresidential minimum lot width 75 ft.
Commercial 3 (Southern Gateway) — C-3 is the Southern Gateway district. The schedule prints N.A. for a one- or two-family residential lot — the base row is the NONRESIDENTIAL standard of 20,000 sq ft, and the 100 ft width recorded above is that row's. Note #: more than one business may be allowed per lot, the number fixed when the special use permit issues, and the Planning Board may modify the side-yard setback for a multiple-use site. THE RESIDENTIAL COVERAGE LIMIT IS A FORMULA, NOT A PERCENTAGE, and it is the same in EVERY district: maximum lot coverage for residential uses including associated accessory uses is 2,400 sq ft PLUS 25% of the lot area up to 3 acres PLUS 5% of the lot area beyond 3 acres. The percentage recorded above is the NONRESIDENTIAL figure, which is the only one this field can hold. The schedule sets a MINIMUM number of storeys as well as a maximum — a floor on building height, which is unusual and has no field. The Historic Overzone (HO) applies the density regulations of the underlying district, so it adds no figures of its own. See § 110-47 for existing undersized lots and § 110-24 for accessory structures and uses. Minimum 2 storey(s), maximum 2 1/2 and 35 ft.
Industrial — The Industrial district's figures are nonresidential. THE RESIDENTIAL COVERAGE LIMIT IS A FORMULA, NOT A PERCENTAGE, and it is the same in EVERY district: maximum lot coverage for residential uses including associated accessory uses is 2,400 sq ft PLUS 25% of the lot area up to 3 acres PLUS 5% of the lot area beyond 3 acres. The percentage recorded above is the NONRESIDENTIAL figure, which is the only one this field can hold. The schedule sets a MINIMUM number of storeys as well as a maximum — a floor on building height, which is unusual and has no field. The Historic Overzone (HO) applies the density regulations of the underlying district, so it adds no figures of its own. See § 110-47 for existing undersized lots and § 110-24 for accessory structures and uses. Minimum 2 storey(s), maximum 3 and 40 ft.
ADUs vs. short-term rentals in Chatham
No local short-term-rental law on record - which is not the same as permission for Village of Chatham. No Village of Chatham STR ordinance found as of Jun 2026. The surrounding Town of Chatham has its own STR law (LL No. 6 of 2023) that does not apply within village boundaries. Village has a general rental property registration chapter only. 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 minimum0.17–0.34 ac — an ADU still has to fit the district's lot and setback envelope.
- UtilityCentral Hudson territory.
- Zoning codeecode360.com/29136282
- Building dept(518) 392-5821
- Last reviewed2026-06-02
ADU FAQ — Chatham, NY
Are ADUs allowed in Chatham, NY?
Village of Chatham has 6 districts. 3 districts prohibit ADUs, 3 require a special-use permit. Check your address with the free ADU checker, or confirm with the building department at (518) 392-5821.
Do I need a special permit for an ADU in Chatham?
It depends on the district: 3 of 6 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 Chatham?
No local short-term-rental law on record - which is not the same as permission for Village of Chatham. 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 Chatham
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 Chatham, priced by size.
More on Chatham: Full zoning for new construction · ADU build cost · House build cost · All Columbia County towns
ADU information for Village of Chatham 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) 392-5821 before relying on any answer. Source: Offsite / Aldo zoning dataset, municipalData.js.