Build an ADU in Hill.
New Hampshire's HB 577 lets you add one accessory dwelling unit on your single-family lot in Hill — by-right. A detached ADU can be up to 950 sf, and ADU setbacks match your lot's single-family setbacks.
3 districts
Each district's single-family setbacks — which your ADU follows. The primary residential district is highlighted.
Verified against the official Hill zoning ordinance · source · 2026-07-07
- Front
- 50 ft
- Side
- 20 ft
- Rear
- 20 ft
- Max coverage
- —
- Min lot
- 130,680 sf (~3.00 ac)
Principal residential district covering most of town ('mainly a district of farms, residences and woodlands'). Permitted uses include one dwelling of up to three families per lot (amended 3/14/96); by special exception, lots exceeding 6 acres may have up to two single-family…
- Front
- 25 ft
- Side
- 20 ft
- Rear
- 20 ft
- Max coverage
- —
- Min lot
- 43,560 sf (~1.00 ac)
District 'mainly of residences and community buildings'. Min lot 1 acre (43,560 sf) with 100 ft frontage; lots of lesser area/frontage platted and recorded before the original ordinance are deemed conforming (V C).
- Front
- 30 ft
- Side
- 10 ft
- Rear
- 10 ft
- Max coverage
- —
- Min lot
- 43,560 sf (~1.00 ac)
Any commercial use or change of use requires Site Plan Review by the Planning Board. Front: min 30 ft between the nearest RIGHT-OF-WAY and the front of any building — may be less if in conformity with the yards of adjoining lots (C Land Requirements 1).
Form-based and downtown districts may use build-to lines instead of fixed setbacks (shown as “—”); verify your parcel's district before you build.
Hill ADU FAQ
Yes. Under NH RSA 674:71-73 (HB 577), one accessory dwelling unit is allowed by-right on single-family lots statewide, including Hill (Merrimack County). A detached ADU can be up to 950 sf.
In Hill's RR zone, ADUs follow the single-family setbacks: 50 ft front, 20 ft side, and 20 ft rear. Hill has 3 zoning districts in total — see the full table below. Confirm your exact zone with the town.