ADU · Delaware County

Can you build an ADU in Delhi, NY?

Town of Delhi has 4 districts. All districts prohibit ADUs. Check your address to confirm the district that applies to your parcel:

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What the Delhi code says

Delhi's code provides no accessory apartment or accessory dwelling unit category. The second-unit route here is a two-family dwelling, permitted in R, R-1 and R-3/5 on a zoning permit, with the two halves as co-equal units rather than a main house plus a subordinate unit.

Conditions the code attaches:

The principal use allowed in each of those districts is stated as one one-family, or one two-family dwelling per lot.
Only one dwelling structure is allowed per lot, so the second unit must be attached. A detached cottage is not available.
§ 512 requires 800 sq ft of habitable floor area per dwelling unit, which rules out small-unit configurations.
§ 516 requires on-site sewage and water meeting the New York State Health Department handbook independently of the district minimum lot size, and says this may require an increase in lot size.
Most of the town drains toward the Cannonsville Reservoir, so New York City watershed rules can apply on top of the septic and water design.
The Development Limitations Overlay (DL) carries no accessory dwelling use of its own.

What the Delhi 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
Residential	0.69 ac	15 / 10 / 10 ft	35 ft	No
Rural I	1 ac	15 / 10 / 10 ft	35 ft	No
Rural III-V	5 ac	15 / 10 / 10 ft	35 ft	No
Development Limitations Overlay	—	—	35 ft	No

Residential - The 25% cap is lot coverage, not footprint: § 502 counts principal buildings, roofed porches, garages, carports, other accessory buildings and paved parking and driveway areas, so a long drive eats into the allowance.

A larger lot may be required: a parcel carrying flood hazard, wetland, steep slope or high elevation is sized by the calculation in § 407H(1) rather than by the minimum lot size shown.
The 15 ft front setback runs from the boundary of a road or right-of-way 50 ft or more in width. On a road or right-of-way under 50 ft, the measure is 40 ft from the centre line.
A maximum lot depth-to-width ratio of 3:1 applies in R, which rules out a deep, narrow lot.
The Village of Delhi is a separate jurisdiction with its own code, and its figures do not govern a parcel in the town.
This lot coverage percentage is not comparable to a neighbouring town's building coverage percentage.

Rural I - The 25% coverage cap counts driveways and paved parking, not just buildings (§ 502). A parcel carrying flood hazard, wetland, steep slope or high elevation is sized by the Development Limitations Overlay calculation, not the one-acre minimum.

The larger-lot sizing method is set out in § 407H(1), so confirm how much buildable area a constrained parcel yields before pricing it.
The 15 ft front setback is measured from the boundary of a road or right-of-way 50 ft or more in width. On a narrower right-of-way, the building must sit 40 ft from the centre line.
A maximum lot depth-to-width ratio of 3:1 applies in R-1, which rules out a deep, narrow lot.
The 200 ft of lot width has to be continuous road frontage.
R-1 covers land within 500 feet of the public highways selected on the district map, and a lot needs direct frontage on and direct access to that road (§ 405A).

Rural III-V - A lot with direct access and frontage on a public highway can use reduced figures under § 406G: 3 acres, 250 ft of frontage and 20% coverage. A public highway is a road maintained by the State, County or Town on or before the 1990 effective date of the ordinance.

Roads that became publicly maintained after adoption in 1990 are not public highways for the purpose of reducing lot dimensions under § 406G.
A lot reached by a private right-of-way is governed by the § 406F figures shown.
Lot coverage under § 502 counts principal buildings, roofed porches, garages, carports, other accessory buildings and paved parking and driveway areas.
The front setback is 15 ft from the boundary of any road or right-of-way 50 ft or more in width, or 40 ft from the centre line of a road or right-of-way under 50 ft.
A maximum lot depth-to-width ratio of 4:1 applies in Rural III-V, which rules out a deep narrow lot.
A parcel carrying flood hazard, wetland, steep slope or high elevation is sized by the Development Limitations Overlay calculation in § 407H(1), which can call for a larger lot.

Development Limitations Overlay - This overlay keeps the underlying district's setbacks, coverage and uses. Density instead comes from net developable acreage, total parcel acreage minus the acreage inside the overlay, divided by the underlying minimum lot size (§ 407H(1)).

Where the entire parcel lies within the overlay, the minimum lot size is twice the underlying district's; whichever of the two methods yields the greater number of lots applies (§ 407H(1)).
No further building construction for any purpose is permitted within a designated flood hazard area, and no zoning permit issues there until the Planning Board grants a special use permit (§ 407G(1)).
Construction within 100 feet of a New York State wetland gets no zoning permit until the applicant holds every applicable DEC approval (§ 407C(1)).
The overlay is triggered by flood hazard areas, freshwater wetlands, slopes of 15% or more, and elevations of 2,000 feet or more (§ 407A).
All of the acreage and lot calculations must be supplied by a licensed surveyor.
The Planning Board decides whether the overlay applies during subdivision review, and its decision can be appealed to the Zoning Board of Appeals.

ADUs vs. short-term rentals in Delhi

Short-term rentals allowed with local rules for Town of Delhi. Renting a home short term falls under the town's bed and breakfast definition, and Schedule I makes bed and breakfast a special permit use in the R, R-1 and R-3/5 districts. That reading is not confirmed, so check with the code enforcement officer first. 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. Municipal source

Good to know

Residential lot minimum0.69–5 ac — an ADU still has to fit the district's lot and setback envelope.
Zoning codetownofdelhiny.gov/sites/default/files/documents/zoning-ordinance.pdf

ADU FAQ — Delhi, NY

Are ADUs allowed in Delhi, NY?

Town of Delhi has 4 districts. All districts prohibit ADUs. Check your address with the free ADU checker, or confirm with the building department.

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

No. No district in Town of Delhi permits an ADU, so there is no permit to apply for. Codes change, so verify with the building department before ruling it out.

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

Short-term rentals allowed with local rules for Town of Delhi. 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 Delhi

Permission is one question and budget is another. An 800 sq ft accessory unit here runs roughly $185k–245k 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 Delhi, priced by size.

How we know this

Sections analyzed: Town of Delhi Zoning Ordinance Schedule I (Residential Uses); §§ 404C, 405C, 406C Permitted Principal Uses; § 512 Minimum Habitable Space; § 516 Sewage Disposal and Water Supply
Districts confirmed: 4 of 4 — every mapped district.
Last reviewed: 2026-08-24
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 Delhi: Full zoning for new construction · ADU build cost · House build cost · ADU rules across Delaware County · All Delaware County towns

ADU information for Town of Delhi is compiled from the municipal code (last reviewed 2026-08-24) 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 municipality before relying on any answer. Source: the Offsite / Aldo zoning dataset.