East Aurora · ADU cost
What it costs to build an ADU in East Aurora, NY
An 800 sq ft accessory dwelling unit in East Aurora 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 East Aurora maps 10 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 East Aurora
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 East Aurora 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 |
|---|---|---|---|---|
| SFR Single-Family Residential | 0.24 ac | 20 / 10 / 20 ft | 35 ft | Special permit |
| LDR Low Density Residential | 0.21 ac | 20 / 8 / 20 ft | 35 ft | Special permit |
| GR General Residential | 0.24 ac | 20 / 10 / 20 ft | 35 ft | Special permit |
| LCR Limited Commercial Residential | 0.21 ac | 20 / 8 / 20 ft | 35 ft | Special permit |
| General Commercial District | 0.21 ac | 25 / 10 / 15 ft | 35 ft | No |
| Neighborhood Commercial District | 0.21 ac | 10 / 10 / 15 ft | 35 ft | No |
| Village-Center Commercial District | 0.21 ac | 0 / 10 / 15 ft | 35 ft | No |
| General Manufacturing District | 1 ac | 25 / 15 / 15 ft | 45 ft | No |
| Village Manufacturing District | 0.3 ac | 10 / 5 / 5 ft | 40 ft | No |
| Open Space District | 3 ac | 35 / 15 / 15 ft | 25 ft | No |
SFR Single-Family Residential - The 20 ft front yard is only the floor: a maximum is set as well, and the average front yard on the block, within a foot either way, may stand in for both. Height and coverage work the same way against the block average.
- A non-residential use is held to a flat 13,000 sq ft on a 100 ft width rather than to the lot shown
- A non-residential rear yard doubles from 25 ft to fifty where the use is adjacent to a residential use
- Neither a two-family nor a multifamily dwelling is permitted in this district at all
- An accessory dwelling unit may reach 20 ft and sits five feet off the side and rear lines; an ordinary accessory structure stops at 15 ft
LDR Low Density Residential, LCR Limited Commercial Residential - The 20 ft front yard is only the floor: a maximum is set as well, and the average front yard on the block, within a foot either way, may stand in for both. Height and coverage work the same way against the block average.
- A non-residential use is held to a flat 13,000 sq ft on a 100 ft width rather than to the lot shown
- A non-residential rear yard doubles from 25 ft to fifty where the use is adjacent to a residential use
- Multifamily needs a special permit, is capped at four units per building and is sized per dwelling unit rather than by lot
- Coverage tightens for multifamily, from 35% to 30%
- An accessory dwelling unit may reach 20 ft and sits five feet off the side and rear lines; an ordinary accessory structure stops at 15 ft
GR General Residential - The 20 ft front yard is only the floor: a maximum is set as well, and the average front yard on the block, within a foot either way, may stand in for both. Height and coverage work the same way against the block average.
- A non-residential use is held to a flat 13,000 sq ft on a 100 ft width rather than to the lot shown
- A non-residential rear yard doubles from 25 ft to fifty where the use is adjacent to a residential use
- Multifamily needs a special permit, is capped at four units per building and is sized per dwelling unit rather than by lot
- An accessory dwelling unit may reach 20 ft and sits five feet off the side and rear lines; an ordinary accessory structure stops at 15 ft
General Commercial District - The front yard is a band rather than a minimum: 25 ft to 75 ft for a dwelling and 10 ft to 75 ft for anything else. Where the use is adjacent to a residential use, the larger of the two published yards applies, and the figures shown are the smaller.
- A non-residential building may reach 45 ft and cover 50% of the lot
- Accessory structures stop at 15 ft and may cover a quarter of the rear yard
Neighborhood Commercial District - A non-residential use needs 35,000 sq ft here, nearly an acre, rather than the lot shown. The front yard is a band: 10 ft to 25 ft for a dwelling and 10 ft to 50 ft for anything else.
- Where the use is adjacent to a residential use, the larger of the two published yards applies, and the figures shown are the smaller
- Accessory structures stop at 15 ft, sit ten feet off the side line rather than five, and may cover a fifth of the rear yard
Village-Center Commercial District - A dwelling may sit right on the street line here, and no further back than 25 ft. A non-residential building must stand back only greater than zero feet, with ten feet preferred to leave room for sidewalks, bike racks and greenspace.
- A commercial use needs 50 ft of lot width against 40 ft for a house
- A non-residential building's height and coverage are settled at site plan review rather than by a figure
- Where the use is adjacent to a residential use, the larger of the two published yards applies, and the figures shown are the smaller
General Manufacturing District - The 15 ft side and rear yards more than triple to fifty where the use is adjacent to a residential one. The front yard is a band of 25 ft to 75 ft rather than a minimum.
- No residential lot standard is published at all: a dwelling that existed before the chapter was adopted counts as a permitted use, but a new one is not contemplated
- Accessory structures stop at 15 ft, sit ten feet off the rear line and five off the side, and may cover a fifth of the rear yard
- Junkyards are prohibited outright
Village Manufacturing District - The five-foot side and rear yards become twenty-five where the use is adjacent to a residential one. The front yard is a band of 10 ft to 25 ft rather than a minimum.
- No residential lot standard is published: a dwelling that existed before the chapter was adopted counts as a permitted use, but a new one is not contemplated
- An upper-floor dwelling unit needs a special permit
- Accessory structures stop at 15 ft and may cover a fifth of the rear yard
- Junkyards and self-storage are prohibited outright
Open Space District - The yards apply only to structures, equipment and other constructed or installed facilities on a lot, not to open land. The 15 ft side and rear yards rise to fifty where the use is adjacent to a residential one.
- An accessory structure stops at 15 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 rentalsShort-term rentals allowed with local rules. The village treats a short-term rental as a bed-and-breakfast, so whatever approval a bed-and-breakfast needs in a district is what a short-term rental needs there. Confirm that approval with the village before listing. Separate question from whether you can build the unit.
- Zoning codeecode360.com/36033243
- Building dept(716) 652-7591
Sizing up a specific parcel in East Aurora?
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 East Aurora runs $204–268/sq ft, about $370k–480k at 1,800 sq ft , plus roughly $5,114 for a conforming lot. See what it costs to build a house in East Aurora.
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) · Farnham (Village) · Gowanda (Village) · Hamburg (Village) · Kenmore (Village) · Lancaster (Village) · North Collins (Village) · Orchard Park (Village) · Sloan (Village) · Springville (Village) · Williamsville (Village)
More on East Aurora: Can you build an ADU here? · Zoning for new construction · Erie County build cost
ADU cost in East Aurora: common questions
How much does it cost to build an ADU in East Aurora, NY?
An 800 sq ft accessory dwelling unit in Village of East Aurora 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 East Aurora?
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 East Aurora?
Village of East Aurora has 10 districts. 6 districts prohibit ADUs, 4 require a special-use permit. Check the specific address with the free ADU checker or confirm with the building department at (716) 652-7591 before you spend money on design.
Can I rent an ADU in East Aurora short term?
Short-term rentals allowed with local rules for Village of East Aurora. 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 East Aurora 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) 652-7591 before relying on any answer. Sources: the Offsite / Aldo cost engine and zoning dataset.