ADU · Monroe County

Can you build an ADU in Chili, NY?

Town of Chili has 9 districts. All districts prohibit ADUs. Check your address to confirm the district that applies to your parcel:

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What the Chili code says

Chili's zoning code provides for no accessory apartment or accessory dwelling unit. The only second-unit route is a two-family dwelling or duplex, which is a principal building rather than an accessory unit and needs a special use permit from the Planning Board.

Conditions the code attaches:

A duplex or two-family dwelling is listed as a special permit use in RA (§ 500-11C(14)), R-1-6 (§ 500-12D(5)) and R-1-12, R-1-15 and R-1-20 (§ 500-13C(7)).
In RM, single-family dwellings and duplexes are allowed only by special permit (§ 500-14).
No building permit or certificate of occupancy issues until the Planning Board approves the special use permit (§ 500-29).
Each unit of a two-family dwelling must meet the single-family floor area standards: 850 sq ft for one bedroom, 1,000 for two, 1,150 for three, 1,300 for four (§ 500-101).
A duplex is defined as two dwelling units side by side (§ 500-101).
Accessory uses under § 500-60 cover garages of up to 1,200 sq ft and create no habitable accessory use. Questions on a specific lot can go to the Building Department at (585) 889-6143.

What the Chili 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
Single-Family Residential	0.14 ac	40 / 8 / 25 ft	35 ft	No
Residential Single-Family	0.28 ac	60 / 10 / 30 ft	35 ft	No
Residential Single-Family	0.34 ac	60 / 10 / 40 ft	35 ft	No
Residential Single-Family	0.46 ac	60 / 10 / 60 ft	35 ft	No
Residential Multiple-Family	0.83 ac	60 / 40 / 30 ft	35 ft	No
Rural Agricultural	1 ac	100 / 30 / 50 ft	35 ft	No
Rural Agricultural	10 ac	100 / 50 / 50 ft	35 ft	No
Agricultural Conservation	2 ac	75 / 50 / 50 ft	35 ft	No
Planned Residential Development	50 ac	—	—	No

Single-Family Residential - The 50 ft width and 40 ft front setback shown apply on ordinary roads. On a lot fronting one of the major highways listed in § 500-59D, the width rises to 60 ft and the front setback to 75 ft.

Residential Single-Family, Residential Single-Family, Residential Single-Family - The 60 ft front setback shown applies on ordinary roads. A lot fronting one of the major highways listed in § 500-59D needs a 75 ft front setback.

Residential Multiple-Family - The 36,000 sq ft minimum is a minimum site, and yield comes from density: 8 units per gross acre where units are built as a linear series with no common hallways or entrances. No building may hold more than 12 units, and no more than six may be in a row.

On a lot fronting one of the major highways listed in § 500-59D, the front setback is 75 ft.
A building must also stand 40 ft from the street line of any interior project road, and side yards on townhouse party-wall lot lines may be zero.
Minimum unit size is 550 sq ft for an efficiency, 700 for a one-bedroom and 850 for a two-bedroom, plus 150 sq ft for each additional bedroom.
No more than 10% of all units may have three bedrooms or more.
Coverage is calculated on the total project area, and all construction needs Planning Board site plan approval.
Single-family dwellings and duplexes need a special permit; apartment houses, condominiums and cooperatives are permitted outright.

Rural Agricultural - The district states no maximum lot coverage.

Rural Agricultural - The 500 ft width is what shapes an RA-10 parcel: ten acres laid out with less than 500 ft of frontage does not comply, however much area it holds.

The district states no maximum lot coverage.

Agricultural Conservation - The 5% coverage cap is the lowest in the town, and on a two-acre lot it allows about 4,350 sq ft of building footprint.

A farm takes a separate column and five times the land: 10 acres on 500 ft of width with a 100 ft front setback, and its coverage allowance is five times as generous at 25%.
The side and rear setbacks are the same 50 ft in both columns.
The figures shown are the standards for a single-family dwelling.

Planned Residential Development - The 50 acres shown is the tract a proposal needs to qualify, not a lot minimum: it must contain at least 50 contiguous acres. Setbacks, height and coverage are set by the Planning Board at site plan review under Article V.

On the serviced part an individual residential lot has both a minimum and a maximum: not less than 10,000 sq ft and not more than 20,000 sq ft, so a larger lot is as non-conforming as a smaller one.
Multifamily units on the serviced part are capped at 10 units per acre.
On the part not served by public sewer and water the minimum residential lot is 5 acres, increased as needed for the separation the County Department of Health requires around a well.
There only agriculture and related residential uses, single-family residences and a customary home occupation are permitted outright.
The application must be filed by the owner, lessee or all joint owners of the whole tract, and the approved plan binds every one of them.
Manufactured homes are the one residential form excluded.

ADUs vs. short-term rentals in Chili

No local short-term-rental law on record - which is not the same as permission for Town of Chili. The Town of Chili has no short-term rental law, and a use missing from a residential district's own closed use lists is not automatically available there. The rule is not confirmed, so confirm with the building department before counting on STR 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 minimum0.14–50 ac — an ADU still has to fit the district's lot and setback envelope.
UtilityRG&E territory.
Zoning codeecode360.com/12423717
Building dept(585) 889-6143

ADU FAQ — Chili, NY

Are ADUs allowed in Chili, NY?

Town of Chili has 9 districts. All districts prohibit ADUs. Check your address with the free ADU checker, or confirm with the building department at (585) 889-6143.

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

No. No district in Town of Chili permits an ADU, so there is no permit to apply for. Codes change, so verify with the building department at (585) 889-6143 before ruling it out.

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

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

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What an ADU costs to build in Chili

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 Chili, priced by size.

How we know this

Sections analyzed: Ch. 500 § 500-11C(14), § 500-12D(5), § 500-13C(7) (two-family dwelling or duplex by special permit); § 500-29; § 500-101
Districts confirmed: 9 of 9 — every mapped district.
Last reviewed: 2026-08-11
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 Chili: Full zoning for new construction · ADU build cost · House build cost · ADU rules across Monroe County · All Monroe County towns

ADU information for Town of Chili is compiled from the municipal code (last reviewed 2026-08-11) 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 (585) 889-6143 before relying on any answer. Source: the Offsite / Aldo zoning dataset.