ADU · Delaware County
Are ADUs allowed in Delaware County, NY?
There is no county-wide answer. In New York an accessory dwelling unit is governed by the town, city or village — so the rule changes at every municipal line, and often between districts inside one town. Below is each of the 10 municipalities in Delaware County, with what its zoning districts actually say.
- 10municipalities with mapped districts
- 5allow an ADU in at least one district
- 3allow one by right somewhere
ADU rules by municipality in Delaware County
Can you build an ADU in Andes, NY?
The only district allows ADUs.
An accessory apartment is permitted on a zoning permit from the Code Enforcement Officer, and the zoning law attaches no size cap or tenancy restriction to it. The deciding limit is the dwelling unit allocation: a tract under 5 acres is allowed one dwelling unit.
Can you build an ADU in Delhi, NY?
All districts prohibit ADUs.
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.
Can you build an ADU in Franklin, NY?
4 districts allow ADUs with occupancy restrictions, 2 require a special-use permit.
Franklin's code has no accessory apartment or accessory dwelling unit, but a two-family dwelling is a permitted use in Rural I, Rural III, Rural V and Hamlet, so a second unit needs only a zoning permit. Only one one- or two-family dwelling is permitted per lot.
Can you build an ADU in Middletown, NY?
5 districts allow ADUs, 1 does not. 1 district has incomplete data - verify with the building department.
Under § 548 a guest home, the town's accessory dwelling unit, carries no owner-occupancy rule, and its occupants may be unrelated to the owner. Each dwelling needs its own approved well and septic system before the building permit.
Can you build an ADU in Sidney, NY?
All districts prohibit ADUs.
An accessory apartment is not among the uses listed in the code, and an unlisted use cannot receive a building permit until the Town Board amends the local law (§ 503). A two-family dwelling is a permitted principal use in SC-R and R, and RA follows those same use lists.
Can you build an ADU in Walton, NY?
3 districts allow ADUs with occupancy restrictions, 1 does not.
An accessory dwelling unit is a permitted accessory use in R-2 (Rural II) and R-5 (Rural V) under § 200-61.1, handled by the code enforcement officer. The owner must keep their primary home in either the principal or the accessory unit, so a non-resident owner cannot use it.
Can you build an ADU in Delhi, NY?
5 districts prohibit ADUs, 4 allow them.
An accessory dwelling unit is permitted where R-1, R-2 or R-3 regulations apply, one per lot, up to 1,000 square feet, inside the principal building or detached. Owner occupancy is not required, and either or both the principal dwelling and the ADU may be rented.
Can you build an ADU in Hancock, NY?
All districts prohibit ADUs.
There is no accessory dwelling unit use. The only way to add units to a house is converting an existing one to a three- or four-family dwelling in R2, by Planning Board special permit with site plan review, which creates co-equal dwellings.
Can you build an ADU in Sidney, NY?
All districts prohibit ADUs.
The Village zoning chapter has no accessory dwelling unit or accessory apartment use. A second unit comes from building a two-family dwelling in R-2 or a multiple-family dwelling in R-3, not from adding an accessory unit to a house.
Can you build an ADU in Walton, NY?
All districts prohibit ADUs.
No district in the Village of Walton lists an accessory dwelling unit or accessory apartment, and § 260-4 prohibits uses that are not specifically listed. In R-S and R-M, a second unit means building a two-family or multifamily dwelling as the principal building.
Delaware County municipalities with no published zoning code
These 4 municipalities have no zoning code we can read online, which means an ADU question has to be answered by the municipality itself.
- Town of Colchester — (607) 363-7918
- Town of Hancock — (607) 637-3651
- Town of Roxbury — (607) 326-7641
- Town of Tompkins — (607) 865-8341
ADU questions people ask about Delaware County
Are ADUs allowed in Delaware County?
There is no single county-wide answer — ADUs are governed by each town, city and village, not by the county. Of the 10 Delaware County municipalities with mapped zoning districts, 5 allow an accessory dwelling unit in at least one district, and 3 allow one by right somewhere. The section for your municipality below gives the specific answer.
Does Delaware County issue ADU permits?
No. Zoning approval and building permits both come from the municipality — the town, city or village — not the county. County health departments do commonly review septic and water supply for a new dwelling unit, which is often the binding constraint on a rural lot.
What size ADU can I build in Delaware County?
Size caps are set per municipality and frequently per district, and they are one of the details most often stated wrongly by national ADU sites. Open your municipality's page below for the code sections analyzed, then confirm the current figure with the building department before you design to it.
What an ADU costs to build in Delaware County
Permission and budget are separate questions. See the Delaware County cost-to-build breakdown for current per-square-foot ranges — an accessory unit runs above a full house per square foot, because the kitchen, bath, panel and heating plant cost the same at any size.
More on Delaware County: Zoning for new construction by town · Cost to build · ADU rules across every county we cover
ADU information for Delaware County is compiled from each municipality's own code , most recently reviewed 2026-08-24, and provided for decision-support only — not legal or architectural advice. Eligibility, size, owner-occupancy and permit conditions vary by district and often carry exceptions; confirm with the municipality before relying on any answer. 1 of the 10 municipalities below still have one or more districts that have not been analyzed, and each says so in its own section. Source: the Offsite / Aldo zoning dataset.