Kenmore · ADU cost
What it costs to build an ADU in Kenmore, NY
An 800 sq ft accessory dwelling unit in Kenmore 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 village 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 Village of Kenmore maps 9 districts that treat accessory units differently from one another, so read the table below as a starting point rather than a verdict.
Check a specific parcel for an ADU in Aldo, free →
ADU cost by size in Kenmore
Standard finish, slab on grade, on a flat and clear part of the lot, general-contractor margin included. These are structure costs at Erie 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 Kenmore 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 |
|---|---|---|---|---|
| Residential Use District No. 1 (One-Family) | — | 25 / 1.5 / - ft | 30 ft | No |
| Residential Use District No. 2 (One/Two-Family) | — | 25 / 1.5 / - ft | 30 ft | No |
| Residential Use District No. 3 (Apartments) | — | 25 / 1.5 / - ft | 30 ft | No |
| Educational Use District | — | 6 / 10 / 10 ft | — | No |
| Restricted Business Use District | — | 6 / - / 10 ft | 30 ft | No |
| General Business Use District | — | 6 / - / 10 ft | 30 ft | No |
| Industrial Use District | — | 6 / - / - ft | — | No |
| Professional Office Use District | — | 25 / 1.5 / - ft | 30 ft | No |
| Planned Unit Development District | — | — | — | — |
Educational Use District - No height limit applies to a building here: the chapter's 30 ft limit reaches the residential districts only. Kenmore states no minimum lot area, no minimum lot width and no lot-coverage percentage, in this district or any other.
- Parking must sit at the rear of the lot only, screened and buffered, with direct access to a public street.
Restricted Business Use District - A parcel must have frontage on Delaware Avenue to be in this district, and no more than 200 ft of depth measured from that right-of-way may be used for a restricted business use. No building may exceed 5,000 sq ft of base floor area, two storeys or 30 ft.
- The code sets no side yard figure: the question goes to the state building code distance-separation requirements, so the answer turns on construction type rather than on zoning.
- The rear yard is ten feet or that same code separation, whichever is greater.
- Vinyl, aluminium, asphalt, plywood and painted masonry exteriors are prohibited outright.
- Kenmore states no minimum lot area, no minimum lot width and no lot-coverage percentage, in this district or any other.
General Business Use District - A parcel must front Elmwood Avenue or Kenmore Avenue to be in this district, and no more than 200 ft of depth measured from that right-of-way may be used for the business use. A building may reach 10,000 sq ft of base floor area, within two storeys and 30 ft.
- The code sets no side yard figure: the question goes to the state building code distance-separation requirements, so the answer turns on construction type rather than on zoning.
- The rear yard is ten feet or that same code separation, whichever is greater.
- Any use not on the district's own list is prohibited outright.
- Kenmore states no minimum lot area, no minimum lot width and no lot-coverage percentage, in this district or any other.
Industrial Use District - The building line on each street is six feet from the adjacent street line, except that on a corner lot the building may extend all the way to the side street line. There is no side yard, rear yard, lot area, lot width, coverage cap or height limit.
- Any use permitted in a residential, business or commercial district is permitted here, along with any industry the fire prevention code does not bar and that does not amount to a nuisance.
Professional Office Use District - The front setback must equal the average of all buildings for 300 ft on each side, and is never less than 25 ft. The side yard turns on how wide the lot is: 18 inches on a lot of 33 ft or less, two feet over 33 up to 38 ft, and three feet above that.
- No rear yard is stated for a principal building.
- The premises must be owned and occupied for practice by a licensed professional, or by a professional corporation at least half of whose shareholders practise there.
- At least a third of the first floor must be in actual professional use, and no more than ten people may be employed at any one premises.
- Store fronts are barred and windows may not cover more than 30% of a facing wall.
Planned Unit Development District - This district does not appear on the village zoning map until a designation is requested and a project is approved, and within it the regulations need not be uniform. Every dimensional standard is set in the local law that maps the district against an approved plan.
Size limits on record in Kenmore
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 Kenmore:
- Residential Use District No. 1 (One-Family)A private garage may not exceed one story or 12 feet, nor 660 sq ft
- Residential Use District No. 2 (One/Two-Family)A private garage may not exceed one story or 12 feet, nor 660 sq ft
- Residential Use District No. 3 (Apartments)A private garage may not exceed one story or 12 feet, nor 660 sq ft
- Educational Use DistrictA private garage may not exceed one story or 12 feet, nor 660 sq ft
- Restricted Business Use DistrictA private garage may not exceed one story or 12 feet, nor 660 sq ft
- General Business Use DistrictA private garage may not exceed one story or 12 feet, nor 660 sq ft
- Industrial Use DistrictA private garage may not exceed one story or 12 feet, nor 660 sq ft
- Professional Office Use DistrictA private garage may not exceed one story or 12 feet, nor 660 sq ft
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. The Village of Kenmore has no local short-term rental law. That is not the same as permission, so confirm with the village before counting on the use. Separate question from whether you can build the unit.
- Zoning codelibrary.municode.com/ny/kenmore/codes/code_of_ordinances?nodeId=MUCO_CH25ZO_ARTIIIREUSDI
- Building dept(716) 873-5700
Sizing up a specific parcel in Kenmore?
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 Kenmore runs $204–268/sq ft, about $370k–480k at 1,800 sq ft . See what it costs to build a house in Kenmore.
ADU cost in nearby towns
All Erie County towns: Buffalo (City) · Lackawanna (City) · Tonawanda (City) · Alden · Amherst · Aurora · Boston · Brant · Cheektowaga · Clarence · Colden · Collins · Concord · Eden · Elma · Evans · Grand Island · Hamburg · Holland · Lancaster · Marilla · Newstead · North Collins · Orchard Park · Sardinia · Tonawanda · Wales · West Seneca · Akron (Village) · Alden (Village) · Angola (Village) · Blasdell (Village) · Depew (Village) · East Aurora (Village) · Farnham (Village) · Gowanda (Village) · Hamburg (Village) · Lancaster (Village) · North Collins (Village) · Orchard Park (Village) · Sloan (Village) · Springville (Village) · Williamsville (Village)
More on Kenmore: Can you build an ADU here? · Zoning for new construction · Erie County build cost
ADU cost in Kenmore: common questions
How much does it cost to build an ADU in Kenmore, NY?
An 800 sq ft accessory dwelling unit in Village of Kenmore 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 Kenmore?
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 Kenmore?
Village of Kenmore has 9 districts. 8 of 9 districts prohibit ADUs. 1 district has incomplete data - verify with the building department at (716) 873-5700. Check the specific address with the free ADU checker before you spend money on design.
Can I rent an ADU in Kenmore short term?
No local short-term-rental law on record - which is not the same as permission for Village of Kenmore. 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 Erie 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 Village of Kenmore vary by district and often carry exceptions this page does not show; zoning last reviewed 2026-09-10; verify with the building department at (716) 873-5700 before relying on any answer. Sources: the Offsite / Aldo cost engine and zoning dataset.