Galway · ADU cost
What it costs to build an ADU in Galway, NY
An 800 sq ft accessory dwelling unit in Galway runs roughly $200k–260k, or about $249–327/sq ft, and that per-square-foot figure sits deliberately above the $204–268/sq ft a full house costs here. An ADU still needs one whole kitchen, one whole bath, its own service panel and its own heating plant no matter how small you draw it, and those costs do not shrink with the floor plan, so they land on half the square footage and push the rate up. Whether the town will let you build one is a separate question from what it costs, and it gets answered parcel by parcel rather than townwide, since the Town of Galway maps 5 districts that treat accessory units differently from one another, so read the table below as a starting point rather than a verdict.
ADU cost by size in Galway
Standard finish, slab on grade, on a flat and clear part of the lot, general-contractor margin included. These are structure costs at Saratoga County pricing, before the service and septic work a second dwelling can trigger.
| Size | Type | $ / sq ft | Estimated total |
|---|---|---|---|
| 400 sq ft | Studio | $331–$433 | $130k–175k |
| 600 sq ft | One bedroom | $276–$362 | $165k–215k |
| 800 sq ft | One bedroom, larger | $249–$327 | $200k–260k |
| 1,000 sq ft | Two bedroom | $233–$305 | $235k–305k |
400 sq ft — One room plus a bath. Garage conversions and small backyard cottages land here.
600 sq ft — The most common detached build - a real bedroom, full kitchen, one bath.
800 sq ft — Room for a proper living area. Still a single bath and one kitchen.
1,000 sq ft — About as large as most codes allow an accessory unit to go.
Why the rate is higher than a house
The systems below are priced for an 800 sq ft unit. The middle column is what each system would cost if it simply shrank with the floor plan; the left column is what it actually costs once you account for the equipment a dwelling needs one of regardless of size. The gap between the two columns is the whole reason small builds price the way they do.
| System | $ / sq ft in an ADU | If it scaled with floor area | Fixed per unit |
|---|---|---|---|
| Site work | $7–$11 | $7 | — |
| Foundation | $16–$23 | $16 | — |
| Framing | $25–$32 | $25 | — |
| Envelope - roof, siding, windows | $32–$41 | $32 | — |
| Plumbing | $28–$34 | $16 | 55% |
| Electrical | $18–$24 | $13 | 35% |
| HVAC | $23–$28 | $15 | 45% |
| Insulation | $7–$9 | $7 | — |
| Interior finishes | $32–$43 | $27 | 15% |
| Millwork & cabinetry | $18–$28 | $11 | 55% |
The fixed-per-unit share is a modeling assumption, not a figure from the code: it is our estimate of how much of each system's budget buys equipment a dwelling needs exactly one of - a kitchen rough-in, a bath group, a service panel, a heating plant - and therefore does not shrink when the unit does. Site work, foundation, framing, envelope and insulation are treated as scaling straight with floor area, which understates the premium slightly, because a small building carries more envelope per square foot of floor than a large one.
What the Galway code says about accessory units
Whether you can build one, and how large, is decided by the district your parcel sits in rather than by the town as a whole. The table shows how each mapped district treats ADUs alongside the lot and setback standards a second unit still has to fit inside. District boundaries and conditions vary, so treat it as a starting point and confirm the district that applies to your parcel.
| District | Min lot | Setbacks F / S / R | Max height | ADU |
|---|---|---|---|---|
| Agricultural Residential (the Town's largest district: a maximum average density of ONE DWELLING UNIT PER 3 ACRES, with a 3-ACRE minimum lot in a conventional non-clustered subdivision, 200 ft of frontage, 50 ft front, side AND rear yards — the only district where all three are equal — a 35 ft height and a 40% maximum coverage. APPENDIX 3A STATES A DENSITY AND SEVERAL DIFFERENT MINIMUM LOT SIZES, AND THEY ARE NOT THE SAME NUMBER. The columns are maximum average density with minimum single lot size; cluster/conservation minimum residential lot; minimum lot for a NON-CLUSTERED or conservation subdivision; minimum non-residential lot; and cluster/conservation minimum lot. minLotSize records the NON-CLUSTERED SUBDIVISION figure because that is the conventional case. Note 5 adds that the minimum may need to RISE to satisfy NYS Department of Health septic and well separation requirements — so on unserviced land the table figure is a floor, not the answer. THE CLUSTER OPTION IS THE REAL LEVER HERE AND IT CUTS THE LOT BY TWO THIRDS: a cluster or conservation subdivision lot may be 1 ACRE rather than 3, and § 115-23 makes such subdivisions eligible for an INCENTIVE DENSITY BONUS on top. Since the underlying density is one unit per three acres, the cluster route delivers the same yield on a third of the lot footprint while banking the remainder as open space — that is the district's entire design and it should be modelled before assuming a conventional layout. NO NON-RESIDENTIAL MINIMUM LOT IS STATED ('Not applicable'), so AR is residential and agricultural land only. THE PERCENTAGE IS 'MAXIMUM LOT COVERED BY STRUCTURES AND IMPERVIOUS SURFACES' — a COMBINED cap, not a building-coverage cap. Driveway, parking and walks count against the same figure the house does, so the buildable footprint is materially smaller than the number suggests. This is a distinct convention from the plain building-coverage maximums used in Ballston, Milton, Stillwater, Moreau and Waterford, and it is NOT comparable to them. KEYHOLE AND FLAG LOTS ARE EXPLICITLY PROVIDED FOR and carry their own acreage: 40 ft of road frontage at the right-of-way with 200 ft at the building line, on 5 acres in AR and 3 acres in RC, RH and C1. The Lake District has no keyhole provision at all. Accessory buildings are capped at 28 ft against the principal 35 ft.) | 3 ac | 50 / 50 / 50 ft | 35 ft | Special permit |
| Residential Core (the Town's densest conventional district: ONE DWELLING UNIT PER HALF ACRE, with a 3/4-ACRE minimum lot in a non-clustered subdivision, only 75 FT of frontage — the shallowest requirement in Galway — 20 ft side and 25 ft rear yards, a 35 ft height and a 30% coverage. APPENDIX 3A STATES A DENSITY AND SEVERAL DIFFERENT MINIMUM LOT SIZES, AND THEY ARE NOT THE SAME NUMBER. The columns are maximum average density with minimum single lot size; cluster/conservation minimum residential lot; minimum lot for a NON-CLUSTERED or conservation subdivision; minimum non-residential lot; and cluster/conservation minimum lot. minLotSize records the NON-CLUSTERED SUBDIVISION figure because that is the conventional case. Note 5 adds that the minimum may need to RISE to satisfy NYS Department of Health septic and well separation requirements — so on unserviced land the table figure is a floor, not the answer. THE FRONT YARD IS A BAND, NOT A FLOOR: Appendix 3B states '25/50 maximum', meaning a 25 ft minimum with a 50 ft MAXIMUM, so a building may not be pushed back beyond 50 ft. That build-to band is what keeps the core's street frontage coherent, and it appears only here and in Rural Hamlet. A cluster or conservation lot drops to 1/2 ACRE, matching the underlying density exactly. NON-RESIDENTIAL USES HAVE NO MINIMUM LOT ('Not applicable') but ARE CAPPED ON FLOOR AREA AT 3,500 SQ FT — the Town controls commercial scale by building size rather than by land here, which is a meaningfully different lever and easy to miss. THE PERCENTAGE IS 'MAXIMUM LOT COVERED BY STRUCTURES AND IMPERVIOUS SURFACES' — a COMBINED cap, not a building-coverage cap. Driveway, parking and walks count against the same figure the house does, so the buildable footprint is materially smaller than the number suggests. This is a distinct convention from the plain building-coverage maximums used in Ballston, Milton, Stillwater, Moreau and Waterford, and it is NOT comparable to them. KEYHOLE AND FLAG LOTS ARE EXPLICITLY PROVIDED FOR and carry their own acreage: 40 ft of road frontage at the right-of-way with 200 ft at the building line, on 5 acres in AR and 3 acres in RC, RH and C1. The Lake District has no keyhole provision at all.) | 0.75 ac | 25 / 20 / 25 ft | 35 ft | Special permit |
| Rural Hamlet (one dwelling unit per half acre with a 1/2-ACRE minimum lot in a non-clustered subdivision — the smallest conventional lot in the Town, smaller even than Residential Core's 3/4 acre — a 25 ft minimum front yard with a 50 ft maximum, a 35 ft height and 30% coverage. APPENDIX 3A STATES A DENSITY AND SEVERAL DIFFERENT MINIMUM LOT SIZES, AND THEY ARE NOT THE SAME NUMBER. The columns are maximum average density with minimum single lot size; cluster/conservation minimum residential lot; minimum lot for a NON-CLUSTERED or conservation subdivision; minimum non-residential lot; and cluster/conservation minimum lot. minLotSize records the NON-CLUSTERED SUBDIVISION figure because that is the conventional case. Note 5 adds that the minimum may need to RISE to satisfy NYS Department of Health septic and well separation requirements — so on unserviced land the table figure is a floor, not the answer. RURAL HAMLET SPLITS EVERY FRONTAGE AND YARD FIGURE BY USE, WHICH NO OTHER GALWAY DISTRICT DOES: frontage is 75 FT FOR A RESIDENCE BUT 200 FT FOR A NON-RESIDENCE; the side yard is 20 ft for a residence and 50 FT for a non-residence; the rear yard 25 ft for a residence and 50 FT for a non-residence. So a shop in the hamlet needs nearly three times the frontage and two and a half times the yards a house does, on the same half-acre lot standard — the district admits commerce into the hamlet while holding it well back from its neighbours. A non-residential lot has its own 1-ACRE minimum, double the residential figure. Non-residential floor area is capped at 3,500 sq ft as in Residential Core. THE PERCENTAGE IS 'MAXIMUM LOT COVERED BY STRUCTURES AND IMPERVIOUS SURFACES' — a COMBINED cap, not a building-coverage cap. Driveway, parking and walks count against the same figure the house does, so the buildable footprint is materially smaller than the number suggests. This is a distinct convention from the plain building-coverage maximums used in Ballston, Milton, Stillwater, Moreau and Waterford, and it is NOT comparable to them. KEYHOLE AND FLAG LOTS ARE EXPLICITLY PROVIDED FOR and carry their own acreage: 40 ft of road frontage at the right-of-way with 200 ft at the building line, on 5 acres in AR and 3 acres in RC, RH and C1. The Lake District has no keyhole provision at all.) | 0.5 ac | 25 / 20 / 25 ft | 35 ft | Special permit |
| Commercial Retail (one dwelling unit per acre with a 2-ACRE minimum lot, 250 FT of frontage — the widest requirement in Galway — a 100 FT FRONT YARD, 50 ft side and rear yards, 35 ft height and 30% coverage. THE 100 FT FRONT SETBACK IS DOUBLE ANYTHING ELSE IN THE TOWN and four times the Residential Core and Rural Hamlet minimum, which together with the 250 ft frontage makes C1 a deep-set highway commercial standard rather than a village one. APPENDIX 3A STATES A DENSITY AND SEVERAL DIFFERENT MINIMUM LOT SIZES, AND THEY ARE NOT THE SAME NUMBER. The columns are maximum average density with minimum single lot size; cluster/conservation minimum residential lot; minimum lot for a NON-CLUSTERED or conservation subdivision; minimum non-residential lot; and cluster/conservation minimum lot. minLotSize records the NON-CLUSTERED SUBDIVISION figure because that is the conventional case. Note 5 adds that the minimum may need to RISE to satisfy NYS Department of Health septic and well separation requirements — so on unserviced land the table figure is a floor, not the answer. THE NON-RESIDENTIAL MINIMUM LOT IS STATED AS A RANGE — '2 TO 10 ACRES' — the only banded lot requirement in the schedule, so the land required scales with the proposal rather than being fixed, and the upper end is five times the lower. Establish where in that band a use falls before sizing anything. Non-residential floor area is capped at 5,000 SQ FT, higher than the 3,500 allowed in RC and RH but still a real ceiling on retail scale. THE PERCENTAGE IS 'MAXIMUM LOT COVERED BY STRUCTURES AND IMPERVIOUS SURFACES' — a COMBINED cap, not a building-coverage cap. Driveway, parking and walks count against the same figure the house does, so the buildable footprint is materially smaller than the number suggests. This is a distinct convention from the plain building-coverage maximums used in Ballston, Milton, Stillwater, Moreau and Waterford, and it is NOT comparable to them. KEYHOLE AND FLAG LOTS ARE EXPLICITLY PROVIDED FOR and carry their own acreage: 40 ft of road frontage at the right-of-way with 200 ft at the building line, on 5 acres in AR and 3 acres in RC, RH and C1. The Lake District has no keyhole provision at all. Note that C1 is a commercial district, so the § 115-52 accessory apartment — which is permitted only in RESIDENTIAL districts — is not available here.) | 2 ac | 100 / 50 / 50 ft | 35 ft | No |
| Lake District (the Galway Lake shoreline district, and THE ONLY GALWAY DISTRICT WITH A DIFFERENT HEIGHT LIMIT: 28 FT against 35 ft everywhere else, with accessory buildings held to 18 ft against 28 ft. That seven-foot reduction is a deliberate lake-view protection and is the district's signature. One dwelling unit per acre with a 1-ACRE minimum lot, 200 ft of frontage and 40% coverage. APPENDIX 3A STATES A DENSITY AND SEVERAL DIFFERENT MINIMUM LOT SIZES, AND THEY ARE NOT THE SAME NUMBER. The columns are maximum average density with minimum single lot size; cluster/conservation minimum residential lot; minimum lot for a NON-CLUSTERED or conservation subdivision; minimum non-residential lot; and cluster/conservation minimum lot. minLotSize records the NON-CLUSTERED SUBDIVISION figure because that is the conventional case. Note 5 adds that the minimum may need to RISE to satisfy NYS Department of Health septic and well separation requirements — so on unserviced land the table figure is a floor, not the answer. ITS YARDS ARE STATED THREE WAYS AND THE DISTINCTION IS BETWEEN NEW AND EXISTING LOTS, NOT JUST WATERFRONT AND NOT: the front yard is 50 FT FOR A NEWLY CREATED LOT, 25 ft for a non-lakefront lot and 50 ft for a lakefront lot; the side yard 50 ft newly created, 25 ft non-lakefront, 25 ft lakefront; the rear yard 50 ft newly created, 15 ft non-lakefront, 15 ft lakefront. So SUBDIVIDING NEW LAKE LOTS TRIGGERS THE DEEPEST ENVELOPE IN THE DISTRICT — 50 ft on all three sides — while an existing non-lakefront lot gets 25-25-15. The recorded figures are the non-lakefront existing-lot case; anyone creating new lots here should use the 50 ft figures throughout. THE LAKE DISTRICT HAS NO KEYHOLE OR FLAG LOT PROVISION AT ALL, where every other district does, so the narrow-frontage workaround is unavailable on the lake. THE PERCENTAGE IS 'MAXIMUM LOT COVERED BY STRUCTURES AND IMPERVIOUS SURFACES' — a COMBINED cap, not a building-coverage cap. Driveway, parking and walks count against the same figure the house does, so the buildable footprint is materially smaller than the number suggests. This is a distinct convention from the plain building-coverage maximums used in Ballston, Milton, Stillwater, Moreau and Waterford, and it is NOT comparable to them. On a lakefront parcel a 40% structures-and-impervious cap is the binding constraint once a drive and parking are counted.) | 1 ac | 25 / 25 / 15 ft | 28 ft | Special permit |
Check my address for ADU feasibility → Free · no account needed to start
Size limits on record in Galway
Where the code states a size cap, it decides which row of the cost table above actually applies to you. These are the caps recorded for Galway:
- Agricultural Residential (the Town's largest district: a maximum average density of ONE DWELLING UNIT PER 3 ACRES, with a 3-ACRE minimum lot in a conventional non-clustered subdivision, 200 ft of frontage, 50 ft front, side AND rear yards — the only district where all three are equal — a 35 ft height and a 40% maximum coverage. APPENDIX 3A STATES A DENSITY AND SEVERAL DIFFERENT MINIMUM LOT SIZES, AND THEY ARE NOT THE SAME NUMBER. The columns are maximum average density with minimum single lot size; cluster/conservation minimum residential lot; minimum lot for a NON-CLUSTERED or conservation subdivision; minimum non-residential lot; and cluster/conservation minimum lot. minLotSize records the NON-CLUSTERED SUBDIVISION figure because that is the conventional case. Note 5 adds that the minimum may need to RISE to satisfy NYS Department of Health septic and well separation requirements — so on unserviced land the table figure is a floor, not the answer. THE CLUSTER OPTION IS THE REAL LEVER HERE AND IT CUTS THE LOT BY TWO THIRDS: a cluster or conservation subdivision lot may be 1 ACRE rather than 3, and § 115-23 makes such subdivisions eligible for an INCENTIVE DENSITY BONUS on top. Since the underlying density is one unit per three acres, the cluster route delivers the same yield on a third of the lot footprint while banking the remainder as open space — that is the district's entire design and it should be modelled before assuming a conventional layout. NO NON-RESIDENTIAL MINIMUM LOT IS STATED ('Not applicable'), so AR is residential and agricultural land only. THE PERCENTAGE IS 'MAXIMUM LOT COVERED BY STRUCTURES AND IMPERVIOUS SURFACES' — a COMBINED cap, not a building-coverage cap. Driveway, parking and walks count against the same figure the house does, so the buildable footprint is materially smaller than the number suggests. This is a distinct convention from the plain building-coverage maximums used in Ballston, Milton, Stillwater, Moreau and Waterford, and it is NOT comparable to them. KEYHOLE AND FLAG LOTS ARE EXPLICITLY PROVIDED FOR and carry their own acreage: 40 ft of road frontage at the right-of-way with 200 ft at the building line, on 5 acres in AR and 3 acres in RC, RH and C1. The Lake District has no keyhole provision at all. Accessory buildings are capped at 28 ft against the principal 35 ft.)THE SIZE RULE IS A DOUBLE CAP and the smaller figure governs: greater than 400 sq ft, and less than either 40% of the dwelling's entire floor area or 1,000 sq ft, whichever is less
- Residential Core (the Town's densest conventional district: ONE DWELLING UNIT PER HALF ACRE, with a 3/4-ACRE minimum lot in a non-clustered subdivision, only 75 FT of frontage — the shallowest requirement in Galway — 20 ft side and 25 ft rear yards, a 35 ft height and a 30% coverage. APPENDIX 3A STATES A DENSITY AND SEVERAL DIFFERENT MINIMUM LOT SIZES, AND THEY ARE NOT THE SAME NUMBER. The columns are maximum average density with minimum single lot size; cluster/conservation minimum residential lot; minimum lot for a NON-CLUSTERED or conservation subdivision; minimum non-residential lot; and cluster/conservation minimum lot. minLotSize records the NON-CLUSTERED SUBDIVISION figure because that is the conventional case. Note 5 adds that the minimum may need to RISE to satisfy NYS Department of Health septic and well separation requirements — so on unserviced land the table figure is a floor, not the answer. THE FRONT YARD IS A BAND, NOT A FLOOR: Appendix 3B states '25/50 maximum', meaning a 25 ft minimum with a 50 ft MAXIMUM, so a building may not be pushed back beyond 50 ft. That build-to band is what keeps the core's street frontage coherent, and it appears only here and in Rural Hamlet. A cluster or conservation lot drops to 1/2 ACRE, matching the underlying density exactly. NON-RESIDENTIAL USES HAVE NO MINIMUM LOT ('Not applicable') but ARE CAPPED ON FLOOR AREA AT 3,500 SQ FT — the Town controls commercial scale by building size rather than by land here, which is a meaningfully different lever and easy to miss. THE PERCENTAGE IS 'MAXIMUM LOT COVERED BY STRUCTURES AND IMPERVIOUS SURFACES' — a COMBINED cap, not a building-coverage cap. Driveway, parking and walks count against the same figure the house does, so the buildable footprint is materially smaller than the number suggests. This is a distinct convention from the plain building-coverage maximums used in Ballston, Milton, Stillwater, Moreau and Waterford, and it is NOT comparable to them. KEYHOLE AND FLAG LOTS ARE EXPLICITLY PROVIDED FOR and carry their own acreage: 40 ft of road frontage at the right-of-way with 200 ft at the building line, on 5 acres in AR and 3 acres in RC, RH and C1. The Lake District has no keyhole provision at all.)THE SIZE RULE IS A DOUBLE CAP and the smaller figure governs: greater than 400 sq ft, and less than either 40% of the dwelling's entire floor area or 1,000 sq ft, whichever is less
- Rural Hamlet (one dwelling unit per half acre with a 1/2-ACRE minimum lot in a non-clustered subdivision — the smallest conventional lot in the Town, smaller even than Residential Core's 3/4 acre — a 25 ft minimum front yard with a 50 ft maximum, a 35 ft height and 30% coverage. APPENDIX 3A STATES A DENSITY AND SEVERAL DIFFERENT MINIMUM LOT SIZES, AND THEY ARE NOT THE SAME NUMBER. The columns are maximum average density with minimum single lot size; cluster/conservation minimum residential lot; minimum lot for a NON-CLUSTERED or conservation subdivision; minimum non-residential lot; and cluster/conservation minimum lot. minLotSize records the NON-CLUSTERED SUBDIVISION figure because that is the conventional case. Note 5 adds that the minimum may need to RISE to satisfy NYS Department of Health septic and well separation requirements — so on unserviced land the table figure is a floor, not the answer. RURAL HAMLET SPLITS EVERY FRONTAGE AND YARD FIGURE BY USE, WHICH NO OTHER GALWAY DISTRICT DOES: frontage is 75 FT FOR A RESIDENCE BUT 200 FT FOR A NON-RESIDENCE; the side yard is 20 ft for a residence and 50 FT for a non-residence; the rear yard 25 ft for a residence and 50 FT for a non-residence. So a shop in the hamlet needs nearly three times the frontage and two and a half times the yards a house does, on the same half-acre lot standard — the district admits commerce into the hamlet while holding it well back from its neighbours. A non-residential lot has its own 1-ACRE minimum, double the residential figure. Non-residential floor area is capped at 3,500 sq ft as in Residential Core. THE PERCENTAGE IS 'MAXIMUM LOT COVERED BY STRUCTURES AND IMPERVIOUS SURFACES' — a COMBINED cap, not a building-coverage cap. Driveway, parking and walks count against the same figure the house does, so the buildable footprint is materially smaller than the number suggests. This is a distinct convention from the plain building-coverage maximums used in Ballston, Milton, Stillwater, Moreau and Waterford, and it is NOT comparable to them. KEYHOLE AND FLAG LOTS ARE EXPLICITLY PROVIDED FOR and carry their own acreage: 40 ft of road frontage at the right-of-way with 200 ft at the building line, on 5 acres in AR and 3 acres in RC, RH and C1. The Lake District has no keyhole provision at all.)THE SIZE RULE IS A DOUBLE CAP and the smaller figure governs: greater than 400 sq ft, and less than either 40% of the dwelling's entire floor area or 1,000 sq ft, whichever is less
- Commercial Retail (one dwelling unit per acre with a 2-ACRE minimum lot, 250 FT of frontage — the widest requirement in Galway — a 100 FT FRONT YARD, 50 ft side and rear yards, 35 ft height and 30% coverage. THE 100 FT FRONT SETBACK IS DOUBLE ANYTHING ELSE IN THE TOWN and four times the Residential Core and Rural Hamlet minimum, which together with the 250 ft frontage makes C1 a deep-set highway commercial standard rather than a village one. APPENDIX 3A STATES A DENSITY AND SEVERAL DIFFERENT MINIMUM LOT SIZES, AND THEY ARE NOT THE SAME NUMBER. The columns are maximum average density with minimum single lot size; cluster/conservation minimum residential lot; minimum lot for a NON-CLUSTERED or conservation subdivision; minimum non-residential lot; and cluster/conservation minimum lot. minLotSize records the NON-CLUSTERED SUBDIVISION figure because that is the conventional case. Note 5 adds that the minimum may need to RISE to satisfy NYS Department of Health septic and well separation requirements — so on unserviced land the table figure is a floor, not the answer. THE NON-RESIDENTIAL MINIMUM LOT IS STATED AS A RANGE — '2 TO 10 ACRES' — the only banded lot requirement in the schedule, so the land required scales with the proposal rather than being fixed, and the upper end is five times the lower. Establish where in that band a use falls before sizing anything. Non-residential floor area is capped at 5,000 SQ FT, higher than the 3,500 allowed in RC and RH but still a real ceiling on retail scale. THE PERCENTAGE IS 'MAXIMUM LOT COVERED BY STRUCTURES AND IMPERVIOUS SURFACES' — a COMBINED cap, not a building-coverage cap. Driveway, parking and walks count against the same figure the house does, so the buildable footprint is materially smaller than the number suggests. This is a distinct convention from the plain building-coverage maximums used in Ballston, Milton, Stillwater, Moreau and Waterford, and it is NOT comparable to them. KEYHOLE AND FLAG LOTS ARE EXPLICITLY PROVIDED FOR and carry their own acreage: 40 ft of road frontage at the right-of-way with 200 ft at the building line, on 5 acres in AR and 3 acres in RC, RH and C1. The Lake District has no keyhole provision at all. Note that C1 is a commercial district, so the § 115-52 accessory apartment — which is permitted only in RESIDENTIAL districts — is not available here.)THE SIZE RULE IS A DOUBLE CAP and the smaller figure governs: greater than 400 sq ft, and less than either 40% of the dwelling's entire floor area or 1,000 sq ft, whichever is less
- Lake District (the Galway Lake shoreline district, and THE ONLY GALWAY DISTRICT WITH A DIFFERENT HEIGHT LIMIT: 28 FT against 35 ft everywhere else, with accessory buildings held to 18 ft against 28 ft. That seven-foot reduction is a deliberate lake-view protection and is the district's signature. One dwelling unit per acre with a 1-ACRE minimum lot, 200 ft of frontage and 40% coverage. APPENDIX 3A STATES A DENSITY AND SEVERAL DIFFERENT MINIMUM LOT SIZES, AND THEY ARE NOT THE SAME NUMBER. The columns are maximum average density with minimum single lot size; cluster/conservation minimum residential lot; minimum lot for a NON-CLUSTERED or conservation subdivision; minimum non-residential lot; and cluster/conservation minimum lot. minLotSize records the NON-CLUSTERED SUBDIVISION figure because that is the conventional case. Note 5 adds that the minimum may need to RISE to satisfy NYS Department of Health septic and well separation requirements — so on unserviced land the table figure is a floor, not the answer. ITS YARDS ARE STATED THREE WAYS AND THE DISTINCTION IS BETWEEN NEW AND EXISTING LOTS, NOT JUST WATERFRONT AND NOT: the front yard is 50 FT FOR A NEWLY CREATED LOT, 25 ft for a non-lakefront lot and 50 ft for a lakefront lot; the side yard 50 ft newly created, 25 ft non-lakefront, 25 ft lakefront; the rear yard 50 ft newly created, 15 ft non-lakefront, 15 ft lakefront. So SUBDIVIDING NEW LAKE LOTS TRIGGERS THE DEEPEST ENVELOPE IN THE DISTRICT — 50 ft on all three sides — while an existing non-lakefront lot gets 25-25-15. The recorded figures are the non-lakefront existing-lot case; anyone creating new lots here should use the 50 ft figures throughout. THE LAKE DISTRICT HAS NO KEYHOLE OR FLAG LOT PROVISION AT ALL, where every other district does, so the narrow-frontage workaround is unavailable on the lake. THE PERCENTAGE IS 'MAXIMUM LOT COVERED BY STRUCTURES AND IMPERVIOUS SURFACES' — a COMBINED cap, not a building-coverage cap. Driveway, parking and walks count against the same figure the house does, so the buildable footprint is materially smaller than the number suggests. This is a distinct convention from the plain building-coverage maximums used in Ballston, Milton, Stillwater, Moreau and Waterford, and it is NOT comparable to them. On a lakefront parcel a 40% structures-and-impervious cap is the binding constraint once a drive and parking are counted.)THE SIZE RULE IS A DOUBLE CAP and the smaller figure governs: greater than 400 sq ft, and less than either 40% of the dwelling's entire floor area or 1,000 sq ft, whichever is less
Costs an ADU adds that a house does not
- Septic and water A second dwelling adds bedrooms to the design flow, which on an unsewered parcel often means expanding or replacing the existing system rather than tapping it. This is the single most common reason an ADU budget moves after design, and it is site-specific enough that no model should quote it - get it evaluated early.
- Utility service National Grid territory. A detached unit needs power run to it, and whether it goes on its own meter or subfeeds the main house changes both the cost and the permit path.
- Access and parking Many codes require an added parking space for the accessory unit, and a detached unit usually needs a driveway extension or a path, both of which count against a lot-coverage or impervious-surface cap.
- Short-term rentalsNo local short-term-rental law on record - which is not the same as permission. No short-term-rental provision exists in the Town of Galway Zoning Law. Chapter 115 defines no short-term rental, vacation rental or transient-occupancy use, and creates no registration or licensing requirement. THE ONE ENUMERATED TRANSIENT USE IS THE BED-AND-BREAKFAST, which has its own dedicated section at § 115-48 rather than merely appearing in a use schedule — worth reading in full before relying on it, since a standalone section usually carries occupancy, parking and owner-residence conditions that a schedule row would not show. Recorded 'unknown' rather than 'prohibited' because the Town has never legislated on short-term rental specifically, and whole-house rental of a permitted single-family dwelling is arguably the residential use itself. Absence of a found STR provision is NOT permission. THE RELEVANT DEMAND HERE IS GALWAY LAKE: the Town has a dedicated Lake District with its own reduced height limit and its own newly-created-lot setback regime, which is exactly the kind of shoreline where seasonal and short-stay rental pressure concentrates, and the code does not address it. Get a written answer from the Zoning Administrator at (518) 882-6070 before underwriting short-term rental income on a Galway Lake parcel. Separately, New York State has required every short-term-rental host to register the unit with the State through the county registry since 2025, regardless of what the municipality allows, and Saratoga County HAS adopted a county-level short-term-rental programme: a 3% occupancy tax and a MANDATORY county registry, covering any room or space in a dwelling let for under 30 consecutive days. Registration runs two years, an unregistered host faces fines of up to $500, and the booking platform is separately liable for processing an unregistered listing — so Airbnb and Vrbo will delist. The City of Saratoga Springs runs its own registry alongside it. Separate question from whether you can build the unit.
- Building dept(518) 882-6070
Sizing up a specific parcel in Galway?
Aldo pulls the exact zoning district, setbacks, and build feasibility for any parcel — before you buy. Enter your email to open Aldo and run your free report.
Building a full house instead?
A standard-finish house in Galway runs $204–268/sq ft, about $370k–480k at 1,800 sq ft , plus roughly $7,030 for a conforming lot. See what it costs to build a house in Galway.
ADU cost in nearby towns
Mechanicville (City)
800 sq ft ≈ $200k–260k
Saratoga Springs (City)
800 sq ft ≈ $200k–260k
Ballston
800 sq ft ≈ $200k–260k
Charlton
800 sq ft ≈ $200k–260k
Clifton Park
800 sq ft ≈ $200k–260k
Corinth
800 sq ft ≈ $200k–260k
All Saratoga County towns: Mechanicville (City) · Saratoga Springs (City) · Ballston · Charlton · Clifton Park · Corinth · Day · Edinburg · Greenfield · Halfmoon · Malta · Milton · Moreau · Northumberland · Providence · Saratoga · Stillwater · Waterford · Wilton · Ballston Spa (Village) · Corinth (Village) · Round Lake (Village) · Schuylerville (Village) · South Glens Falls (Village) · Stillwater (Village) · Victory (Village) · Waterford (Village)
More on Galway: Can you build an ADU here? · Zoning for new construction · Saratoga County build cost
ADU cost in Galway: common questions
How much does it cost to build an ADU in Galway, NY?
An 800 sq ft accessory dwelling unit in Town of Galway runs roughly $200k–260k at a standard finish, general-contractor margin included. A 400 sq ft studio runs about $130k–175k. Those are structure costs on an easy site and do not include the septic, water or electrical service work a second unit often triggers.
Why does an ADU cost more per square foot than a house in Galway?
Because a lot of a dwelling's cost is per dwelling, not per square foot. One kitchen, one bath group, one service panel and one heating plant cost about the same in an 800 sq ft cottage as in a 1,800 sq ft house, so on the smaller unit they get spread over less than half the floor area. That is why an ADU here prices at $249–327/sq ft against $204–268/sq ft for a full house, even though it is the same trades doing the same work.
Are ADUs allowed in Galway?
Town of Galway has 5 districts. 4 districts allow ADUs with a special-use permit, 1 does not. Check the specific address with the free ADU checker or confirm with the building department at (518) 882-6070 before you spend money on design.
Can I rent an ADU in Galway short term?
No local short-term-rental law on record - which is not the same as permission for Town of Galway. ADU rules and short-term-rental rules are set separately, so a unit you are allowed to build is not automatically one you are allowed to rent nightly. Confirm both before you underwrite the build on short-term-rental income.
ADU costs are modeled estimates in current 2026 dollars at the Saratoga County regional index, general-contractor margin included, derived from Offsite's cost engine with a stated adjustment for the equipment a dwelling needs one of regardless of size. They are planning numbers for decision-support only - not a bid, quote, or guarantee, and not legal, architectural or engineering advice. They cover the structure and exclude septic expansion, utility service runs, site work beyond a flat and clear pad, and permit fees. ADU eligibility, size, owner-occupancy and permit conditions in the Town of Galway vary by district and often carry exceptions this page does not show; zoning last reviewed 2026-08-02; verify with the building department at (518) 882-6070 before relying on any answer. Sources: Offsite / Aldo cost engine (costEngine.js + constants.js); zoning dataset (municipalData.js).