ADU · Rockland County
Can you build an ADU in Clarkstown, NY?
Town of Clarkstown has 16 districts. All districts prohibit ADUs. Check your address to confirm the district that applies to your parcel:
What the Clarkstown 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 |
|---|---|---|---|---|
| Conservation Density Residence | 3.67 ac | 50 / 50 / 100 ft | 35 ft | No |
| Low Density Residence | 1.84 ac | 50 / 30 / 50 ft | 35 ft | No |
| Low Density Residence | 0.92 ac | 50 / 30 / 50 ft | 35 ft | No |
| Medium Density Residence | 0.52 ac | 35 / 20 / 35 ft | 35 ft | No |
| Medium Density Residence | 0.34 ac | 30 / 20 / 35 ft | 35 ft | No |
| Medium High Density Residence | 0.23 ac | 30 / 20 / 30 ft | 35 ft | No |
| Laboratory Office | 4.59 ac | 100 / 60 / 100 ft | — | No |
| Professional Office | 0.69 ac | 35 / 25 / 50 ft | — | No |
| Local Shopping | 0.18 ac | 25 / - / 25 ft | — | No |
| Community Shopping | 0.23 ac | 30 / - / 50 ft | — | No |
| Major Regional Shopping | 30 ac | 40 / 25 / 50 ft | — | No |
| Light Industrial Office | 2.3 ac | 80 / 60 / 50 ft | — | No |
| Manufacturing | 1.38 ac | 50 / 50 / 50 ft | — | No |
| Planned Economic Development | 2.3 ac | — | 48 ft | No |
| Commercial Office | 2.3 ac | 80 / 60 / 50 ft | 40 ft | No |
| Commercial Office Support | 0.23 ac | 30 / 15 / 25 ft | 35 ft | No |
ADUs vs. short-term rentals in Clarkstown
Short-term rentals prohibited for Town of Clarkstown. Prohibited. Town Code Ch. 157, Art. X "Prohibition on Short-Term Rentals of Residential Dwellings" bans rentals under 29 consecutive nights in all residentially zoned districts (added 12-11-2020 by L.L. No. 7-2020; amended 3-8-2022 by L.L. No. 1-2022, which sunset previously issued permits). Lawfully permitted hotels/motels and B&Bs are exempt. First-offense fines $3,500-$5,000. There is no permit path. Confirm with the Building Department at (845) 639-2100 before listing a property. Separately, since 2025 New York State requires every short-term-rental host to register the unit with the State through the county registry, regardless of what the municipality allows. 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 minimum0.23–3.67 ac — an ADU still has to fit the district's lot and setback envelope.
- UtilityOrange & Rockland territory.
- Building dept(845) 639-2100
- Last reviewed2026-08-16
ADU FAQ — Clarkstown, NY
Are ADUs allowed in Clarkstown, NY?
Town of Clarkstown has 16 districts. All districts prohibit ADUs. Check your address with the free ADU checker, or confirm with the building department at (845) 639-2100.
Do I need a special permit for an ADU in Clarkstown?
No. No district in Town of Clarkstown permits an ADU, so there is no permit to apply for. Codes change, so verify with the building department at (845) 639-2100 before ruling it out.
Can I use an ADU as a short-term rental in Clarkstown?
Short-term rentals prohibited for Town of Clarkstown. 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.
What an ADU costs to build in Clarkstown
Permission is one question and budget is another. An 800 sq ft accessory unit here runs roughly $225k–295k 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 Clarkstown, priced by size.
More on Clarkstown: Full zoning for new construction · ADU build cost · House build cost · All Rockland County towns
ADU information for Town of Clarkstown is compiled from the municipal code (last reviewed 2026-08-16) 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 (845) 639-2100 before relying on any answer. Source: Offsite / Aldo zoning dataset, municipalData.js.