What it costs to build an ADU in Ballston, NY

HR Hamlet Residential - The front yard is a band rather than a floor: at least 30 ft and no more than 50 ft, so a building may not be pushed back past 50 ft. The 20,000 sq ft minimum on 65 ft of frontage applies with water and sewer.

• Without water and sewer the standard is a density, 1 dwelling per 1 acre, against 20,000 sq ft with both, and the frontage rises from 65 ft to 100 ft; coverage, yards and height do not move.
• Inside the watershed protection overlay the maximum coverage drops from 40% to 20%.
• A two-family dwelling and a townhouse are both available, by site plan review rather than by right.

BLR Ballston Lake Residential - Taking part in the purchase of development rights programme under § 138-168 cuts the two-acre minimum to one acre without utilities, or to a third of an acre with water and sewer.

• With water and sewer the purchase of development rights bonus cuts the minimum lot to 0.3333 acres, a sixfold increase in density; confirm eligibility with the Town before relying on it.
• The two acres holds with or without water and sewer, so the lot minimum here does not move with service.
• Net acreage calculation is required, so constrained land comes out of the yield before the two acres is applied, and average lot size is allowed.

MU Route 50/67 Mixed Use - A commercial building is capped at 10,000 sq ft of footprint per lot, rising to 40,000 sq ft with the purchase of development rights bonus under § 138-168. That cap, rather than the coverage percentage, is what limits commercial scale here.

• The front yard is a band: at least 20 ft and no more than 70 ft, so a building may not be set back past 70 ft.
• Height is 40 feet, or 3 stories if permitted by the Fire Department.
• Design standards for all the mixed-use centre districts apply under § 138-17.
• An accessory structure under 200 sq ft takes a six-foot rear and side yard.
• Footings must sit one foot above the seasonal high groundwater mark, which is a real cost on the town's wetter ground.

BHC Burnt Hills Commercial - For a property not fronting Route 50 the neighbours set the building line: the setbacks of new buildings must be proximal to adjoining structures, with variations inside the established standards subject to Planning Board approval.

• Otherwise the front yard is a band: at least 20 ft and no more than 70 ft.
• A commercial building is capped at 15,000 sq ft of footprint per lot, and the density and square footage bonus is not available in this district.
• Design standards for all the mixed-use centre districts apply under § 138-17.
• An accessory structure under 200 sq ft takes a six-foot rear and side yard.
• Footings must sit one foot above the seasonal high groundwater mark, which is a real cost on the town's wetter ground.

MU BL Mixed Use Ballston Lake - The code states no number for the front yard: for a property fronting Route 146A the setbacks of new buildings must be proximal to adjoining structures, with variations inside the established standards subject to Planning Board approval.

• A commercial building is capped at 2,000 sq ft of footprint per lot, rising to 5,000 sq ft with the purchase of development rights bonus. That cap, not the coverage percentage, limits scale.
• Design standards for the mixed use districts apply under § 138-17.
• An accessory structure under 200 sq ft takes a six-foot rear and side yard.
• Footings must sit one foot above the seasonal high groundwater mark, which is a real cost on the town's wetter ground.

BLW Ballston Lake Waterfront - The one-acre minimum on 150 ft of frontage applies with water and sewer; without them the lot must be two acres on 175 ft. The 60 ft front yard, 12 ft side, 15 ft rear, 40 ft height and 15% coverage hold either way.

• No density bonus is allowed here, so the bonus that cuts the minimum lot elsewhere in the town cannot be used on the waterfront.
• Fifteen percent on a one-acre lot is about 6,500 sq ft of footprint for everything on the parcel.
• An accessory structure under 200 sq ft takes a six-foot rear and side yard.
• Footings must sit one foot above the seasonal high groundwater mark, which is a real cost on the town's wetter ground.

B Business - A commercial building is capped at 5,000 sq ft of footprint per lot, rising to 15,000 sq ft with the purchase of development rights bonus. That cap, rather than the coverage percentage, is what limits commercial scale here.

• The front yard is a band: at least 35 ft and no more than 70 ft.
• There is no by-right route to multiple dwellings: they are reachable only through the floating senior housing district of Article XIII, which carries a 20-acre qualifying site.
• Design standards apply under § 138-31.
• An accessory structure under 200 sq ft takes a six-foot rear and side yard.
• Footings must sit one foot above the seasonal high groundwater mark, which is a real cost on the town's wetter ground.

RHT Rural Highway Transition - A commercial building is capped at 5,000 sq ft of footprint per lot, and the density bonus that lifts that cap elsewhere is not allowed in this district. The front yard is a band: at least 35 ft and no more than 70 ft.

• Inside the watershed protection overlay the maximum coverage drops from 30% to 20%.
• Design standards apply under § 138-31.
• An accessory structure under 200 sq ft takes a six-foot rear and side yard.
• Footings must sit one foot above the seasonal high groundwater mark, which is a real cost on the town's wetter ground.

R Rural - The one-acre minimum is not the binding constraint: density is one dwelling per five acres, so a fifty-acre parcel yields ten dwellings rather than fifty, and the acre only says how small each of those ten lots may be.

• Net acreage calculation is required, so constrained land comes out before the five-acre rate is applied and the yield on a wet or steep parcel is lower again. Average lot size is allowed.
• A major subdivision must be a conservation subdivision, which expressly allows flexible lot sizes and setbacks, so the 100 ft front, 50 ft side and 60 ft rear yards describe a single-lot proposal.
• § 138-19 sets a separate minimum frontage for flag lots.
• Inside the watershed protection overlay the maximum coverage drops from 20% to 15%.
• A commercial building is capped at 2,500 sq ft of footprint per lot, and no density bonus is allowed.
• Footings must sit one foot above the seasonal high groundwater mark, and an accessory structure under 200 sq ft takes a six-foot rear and side yard.

LI Light Industrial - The 50 ft front setback is only for a lot fronting a municipal or private interior road within the district: on any state or county roadway every building setback must be at least 100 ft from the front property line.

• Where the district adjoins a residential district boundary line a 100 ft buffer is required, on top of the 30 ft side and rear yards.
• The minimum lot area is set by § 138-39B rather than by a district figure.
• There is no cap on commercial building footprint here, which with the 60 ft of height is what makes an industrial-scale building possible.
• An accessory structure under 200 sq ft takes a six-foot rear and side yard.
• Footings must sit one foot above the seasonal high groundwater mark, which is a real cost on the town's wetter ground.

SH Senior Housing - The 20 acres is a qualifying site area for creating the district over a parcel, not a minimum for each lot: this is a floating district created parcel by parcel under Article XIII § 138-51, and the only route to multiple dwellings in the B district.

• At least 60% of the parcel, or of the combined parcels, must be open space under § 138-51J(2)(f).
• Any individual building is capped at a 20,000 sq ft footprint under § 138-125, raised only by taking part in the Green Energy Incentive Program under Article XVII.
• A building containing single-family attached, townhouse or multifamily units may be no more than 200 linear feet long, whatever the unit count.
• The 80 ft front setback is measured from adjoining roads and the 100 ft side and rear from adjoining properties, and the Town Board may vary the side and rear setbacks and the building separation.
• The Planning Board may require a vegetated or landscaped buffer screening the development from Route 50 or Route 67.
• Design standards apply under Article XXVI and, to the maximum extent practical, § 138-17.