ADU · Saratoga County

Can you build an ADU in Halfmoon, NY?

Town of Halfmoon has 12 districts. All districts prohibit ADUs. Check your address to confirm the district that applies to your parcel:

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What the Halfmoon code says

An accessory dwelling unit is not an available use in any Halfmoon district. A two-family dwelling is a different route to a second unit: it is a special-permit use in A-R and R-1 and a permitted use in R-3.

Conditions the code attaches:

In A-R and R-1 a two-family dwelling needs 40,000 sq ft regardless of utilities.
Confirm with Building & Code Enforcement at (518) 371-7410 x2260.

What the Halfmoon 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
A-R Agricultural Residential	0.46 ac	50 / 15 / 50 ft	35 ft	No
R-1 Residential	0.46 ac	50 / 15 / 50 ft	35 ft	No
R-2 Residence	0.46 ac	50 / 15 / 50 ft	35 ft	No
R-3 Residence	0.46 ac	50 / 15 / 50 ft	35 ft	No
PO-R Professional Office Residential	0.57 ac	70 / 10 / 30 ft	35 ft	No
C-1 Commercial	0.57 ac	50 / 15 / 25 ft	35 ft	No
LI-C Light Industrial Commercial	0.92 ac	50 / 15 / 30 ft	35 ft	No
M-1 Industrial	0.92 ac	50 / 15 / 25 ft	35 ft	No
M-2 Industrial	0.92 ac	50 / 15 / 25 ft	35 ft	No
NB-1 Neighborhood Business	0.46 ac	50 / 10 / 30 ft	35 ft	No
W-1 Waterfront	0.57 ac	50 / 15 / 25 ft	35 ft	No
W-2 Waterfront	0.57 ac	50 / 15 / 25 ft	35 ft	No

A-R Agricultural Residential - The minimum lot shown needs public sewer and water. With only one of them a lot needs 30,000 sq ft on 150 ft of width, and with neither 40,000 sq ft on 150 ft.

On Route 9 (including at Grooms Road and at Guideboard Road), Route 236 and Routes 4 and 32 (both sides), Schedule A requires 25,000 sq ft on 150 ft of width, whatever the district.
On Route 146 a lot needs 28,000 sq ft on 150 ft of width with a 70 ft front yard, and on the west side of Routes 4 and 32 the front yard is 70 ft, whatever the district.
A farm needs 80,000 sq ft on 150 ft of width, with 30% coverage, 50 ft side yards and 100 ft for both sides combined.
Special-permit uses need larger lots and at least 20% green space: 120,000 sq ft on 200 ft for a church, and 80,000 sq ft on 150 ft for a public utility or cemetery.
A marina, funeral home or recreation area-club needs 40,000 sq ft on 200 ft at 25% coverage, and a convalescent or nursing home 2,000 sq ft per bed on 200 ft.
The Planning Board may require larger lots for any special-permit use, depending on the availability of public water and/or sewer.

R-1 Residential - The minimum lot shown needs public sewer and water. With only one of them a lot needs 30,000 sq ft on 150 ft of width, and with neither 40,000 sq ft on 150 ft.

On Route 9 (including at Grooms Road and at Guideboard Road), Route 236 and Routes 4 and 32 (both sides), Schedule A requires 25,000 sq ft on 150 ft of width, whatever the district.
On Route 146 a lot needs 28,000 sq ft on 150 ft of width with a 70 ft front yard, and on the west side of Routes 4 and 32 the front yard is 70 ft, whatever the district.
Special-permit uses need larger lots: 120,000 sq ft for a church, 40,000 sq ft on 200 ft for a marina, funeral home or recreation area-club, and 80,000 sq ft for a public utility or cemetery.
A convalescent or nursing home needs 2,000 sq ft per bed.
The Planning Board may require larger lots for any of these special-permit uses, depending on utility availability.

R-2 Residence - The minimum lot shown needs public sewer and water. With only one of them a lot needs 30,000 sq ft on 150 ft of width, and with neither 40,000 sq ft on 150 ft.

A mobile home park is a special-permit use here, the only district where one is possible. Its standards are set by the Trailer Ordinance of the Town of Halfmoon, not by the zoning schedule.
On Route 9 (including at Grooms Road and at Guideboard Road), Route 236 and Routes 4 and 32 (both sides), Schedule A requires 25,000 sq ft on 150 ft of width, whatever the district.
On Route 146 a lot needs 28,000 sq ft on 150 ft of width with a 70 ft front yard, and on the west side of Routes 4 and 32 the front yard is 70 ft, whatever the district.

R-3 Residence - The minimum lot shown needs public sewer and water. With only one of them a lot needs 30,000 sq ft on 150 ft of width, and with neither 40,000 sq ft on 150 ft.

A three-family dwelling needs 30,000, 40,000 or 50,000 sq ft and a four-family 40,000, 50,000 or 60,000 sq ft, by utility service, both on 150 ft of width.
Three- and four-family dwellings are held to 25% coverage and a 30 ft rear yard rather than 50 ft, and work out at 10,000 sq ft a unit only when fully serviced.
All uses allowed by special permit in R-1 are also admitted here, on the R-1 figures for each use.
On Route 9 (including at Grooms Road and at Guideboard Road), Route 236 and Routes 4 and 32 (both sides), Schedule A requires 25,000 sq ft on 150 ft of width, whatever the district.
On Route 146 a lot needs 28,000 sq ft on 150 ft of width with a 70 ft front yard, and on the west side of Routes 4 and 32 the front yard is 70 ft, whatever the district.

PO-R Professional Office Residential - The minimum lot shown needs public sewer and water. With only one of them a lot needs 35,000 sq ft, and with neither 45,000 sq ft.

At least 20% of the lot must be green space, a minimum planted area that is separate from the building coverage cap.
All uses allowed by special permit in R-1 are also admitted here, on the R-1 figures for each use.
On Route 9 (including at Grooms Road and at Guideboard Road), Route 236 and Routes 4 and 32 (both sides), Schedule A requires 25,000 sq ft on 150 ft of width, whatever the district.
On Route 146 a lot needs 28,000 sq ft on 150 ft of width with a 70 ft front yard, and on the west side of Routes 4 and 32 the front yard is 70 ft, whatever the district.

C-1 Commercial - The 25,000 sq ft minimum lot requires site plan approval, the ability to connect to public sewer and water, and room to meet parking setback and green space requirements. With only one utility a lot needs 35,000 sq ft, and with neither 45,000 sq ft.

Where the lot is next to a residential district, the combined side yard and the rear yard follow the transition yard requirements of § 165-32F.
The 50% building coverage is subject to site plan review and approval.
A building taller than 35 ft may be submitted to the Planning Board as part of the site plan.
At least 20% of the lot must be green space, a minimum planted area that is separate from the building coverage cap.
On Route 9 (including at Grooms Road and at Guideboard Road), Route 236 and Routes 4 and 32 (both sides), Schedule A requires 25,000 sq ft on 150 ft of width, whatever the district.
On Route 146 a lot needs 28,000 sq ft on 150 ft of width with a 70 ft front yard, and on the west side of Routes 4 and 32 the front yard is 70 ft, whatever the district.

LI-C Light Industrial Commercial, M-1 Industrial - The minimum lot shown needs public sewer and water. With only one of them a lot needs 50,000 sq ft, and with neither 60,000 sq ft.

Where the lot is next to a residential district, the combined side yard and the rear yard follow the transition yard requirements of § 165-32F.
The 50% building coverage is subject to site plan review and approval.
A building taller than 35 ft may be submitted to the Planning Board as part of the site plan.
At least 20% of the lot must be green space, a minimum planted area that is separate from the building coverage cap.
On Route 9 (including at Grooms Road and at Guideboard Road), Route 236 and Routes 4 and 32 (both sides), Schedule A requires 25,000 sq ft on 150 ft of width, whatever the district.
On Route 146 a lot needs 28,000 sq ft on 150 ft of width with a 70 ft front yard, and on the west side of Routes 4 and 32 the front yard is 70 ft, whatever the district.

M-2 Industrial - The minimum lot shown needs public sewer and water. With only one of them a lot needs 50,000 sq ft, and with neither 60,000 sq ft; a residential use follows the R-1 and A-R residential figures instead.

For a residential use that means 20,000 sq ft on 100 ft with public sewer and water, 30,000 sq ft on 150 ft with one, 40,000 sq ft on 150 ft with neither, 20% coverage and a 50 ft rear yard.
Where the lot is next to a residential district, the combined side yard and the rear yard follow the transition yard requirements of § 165-32F.
The 50% building coverage is subject to site plan review and approval.
A building taller than 35 ft may be submitted to the Planning Board as part of the site plan.
At least 20% of the lot must be green space, a minimum planted area that is separate from the building coverage cap.
On Route 9 (including at Grooms Road and at Guideboard Road), Route 236 and Routes 4 and 32 (both sides), Schedule A requires 25,000 sq ft on 150 ft of width, whatever the district.

NB-1 Neighborhood Business - The Planning Board may consider a lot as small as 10,000 sq ft under the conditions set in § 165-17B(3). The 20,000 sq ft minimum is a single figure that does not change with utility service.

At least 20% of the lot must be green space, a minimum planted area that is separate from the building coverage cap.
On Route 9 (including at Grooms Road and at Guideboard Road), Route 236 and Routes 4 and 32 (both sides), Schedule A requires 25,000 sq ft on 150 ft of width, whatever the district.
On Route 146 a lot needs 28,000 sq ft on 150 ft of width with a 70 ft front yard, and on the west side of Routes 4 and 32 the front yard is 70 ft, whatever the district.

W-1 Waterfront - A dwelling here must meet the R-1 and A-R residential figures, not the commercial ones shown: 20,000 sq ft on 100 ft with public sewer and water, rising to 40,000 sq ft on 150 ft with neither, at 20% coverage and a 50 ft rear yard.

For other uses the 25,000 sq ft lot requires site plan approval, the ability to connect to public sewer and water, and room to meet parking setback and green space requirements.
With only one utility a non-residential lot needs 35,000 sq ft, and with neither 45,000 sq ft.
Where the lot is next to a residential district, the combined side yard and the rear yard follow the transition yard requirements of § 165-32F.
The 50% building coverage is subject to site plan review and approval.
A building taller than 35 ft may be submitted to the Planning Board as part of the site plan.
On Route 9 (including at Grooms Road and at Guideboard Road), Route 236 and Routes 4 and 32 (both sides), Schedule A requires 25,000 sq ft on 150 ft of width, whatever the district.

W-2 Waterfront - The figures shown apply to uses also permitted in W-1. A use also permitted in M-2 needs 40,000, 50,000 or 60,000 sq ft by utility service, and a dwelling must meet the R-1 and A-R residential figures.

For a dwelling that means 20,000 sq ft on 100 ft of width with public sewer and water and 40,000 sq ft on 150 ft with neither, at 20% coverage with a 50 ft rear yard.
For uses also permitted in W-1, the 25,000 sq ft lot requires site plan approval, the ability to connect to public sewer and water, and room to meet parking setback and green space requirements.
For uses also permitted in W-1, a lot needs 35,000 sq ft with only one utility and 45,000 sq ft with neither.
Where the lot is next to a residential district, the combined side yard and the rear yard follow the transition yard requirements of § 165-32F.
A building taller than 35 ft may be submitted to the Planning Board as part of the site plan.
On Route 9 (including at Grooms Road and at Guideboard Road), Route 236 and Routes 4 and 32 (both sides), Schedule A requires 25,000 sq ft on 150 ft of width, whatever the district.

ADUs vs. short-term rentals in Halfmoon

No local short-term-rental law on record - which is not the same as permission for Town of Halfmoon. The Town of Halfmoon has no local short-term rental law, and that is not the same as permission. Confirm with Building & Code Enforcement 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 minimum0.46 ac — an ADU still has to fit the district's lot and setback envelope.
UtilityNational Grid territory.
Zoning codeecode360.com/6503934
Building dept(518) 371-7410 x2260

ADU FAQ — Halfmoon, NY

Are ADUs allowed in Halfmoon, NY?

Town of Halfmoon has 12 districts. All districts prohibit ADUs. Check your address with the free ADU checker, or confirm with the building department at (518) 371-7410 x2260.

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

No. No district in Town of Halfmoon permits an ADU, so there is no permit to apply for. Codes change, so verify with the building department at (518) 371-7410 x2260 before ruling it out.

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

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

Permission is one question and budget is another. An 800 sq ft accessory unit here runs roughly $200k–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 Halfmoon, priced by size.

How we know this

Zoning code: ecode360.com/6503934
Districts confirmed: 12 of 12 — every mapped district.
Last reviewed: 2026-07-27
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 Halfmoon: Full zoning for new construction · ADU build cost · House build cost · ADU rules across Saratoga County · All Saratoga County towns

ADU information for Town of Halfmoon is compiled from the municipal code (last reviewed 2026-07-27) 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) 371-7410 x2260 before relying on any answer. Source: the Offsite / Aldo zoning dataset.