Build an ADU in Piermont.
New Hampshire's HB 577 lets you add one accessory dwelling unit on your single-family lot in Piermont — 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 Piermont zoning ordinance · source · 2026-07-07
- Front
- 50 ft
- Side
- 20 ft
- Rear
- 20 ft
- Max coverage
- —
- Min lot
- 43,560 sf (~1.00 ac)
Principal residential district: 'All of the Town not contained within the boundaries of the Lake and Village Districts' (Art VIII Sec 4.6, Rural District). FRONT setback 50 ft is measured FROM THE CENTERLINE of any road or highway, NOT from the ROW/lot line (Sec 4.5.c) - so…
- Front
- 50 ft
- Side
- 20 ft
- Rear
- 20 ft
- Max coverage
- —
- Min lot
- 43,560 sf (~1.00 ac)
Village District along Routes 10/25/25C near the traffic-light center of town (boundary metes-and-bounds at Art VIII Sec 4.6, Village District). Same town-wide Minimal Dimensional Requirements apply (Art VIII Sec 4.5): front 50 ft FROM ROAD CENTERLINE (Sec 4.5.c), side 20 ft…
- Front
- 50 ft
- Side
- 20 ft
- Rear
- 20 ft
- Max coverage
- —
- Min lot
- 43,560 sf (~1.00 ac)
Lake District in the northeast (Lily Pond area), boundary metes-and-bounds at Art VIII Sec 4.6, Lake District. Same town-wide Minimal Dimensional Requirements apply (Art VIII Sec 4.5): front 50 ft FROM ROAD CENTERLINE (Sec 4.5.c), side 20 ft (Sec 4.5.e; 6 ft for detached…
Form-based and downtown districts may use build-to lines instead of fixed setbacks (shown as “—”); verify your parcel's district before you build.
Piermont 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 Piermont (Grafton County). A detached ADU can be up to 950 sf.
In Piermont's R zone, ADUs follow the single-family setbacks: 50 ft front, 20 ft side, and 20 ft rear. Piermont has 3 zoning districts in total — see the full table below. Confirm your exact zone with the town.