Build an ADU in Waterville Valley.
New Hampshire's HB 577 lets you add one accessory dwelling unit on your single-family lot in Waterville Valley — by-right. A detached ADU can be up to 950 sf, and ADU setbacks match your lot's single-family setbacks.
9 districts
Each district's single-family setbacks — which your ADU follows. The primary residential district is highlighted.
Verified against the official Waterville Valley zoning ordinance · source · 2026-07-07
- Front
- 35 ft
- Side
- 20 ft
- Rear
- 20 ft
- Max coverage
- 25% impervious
- Min lot
- 21,780 sf (~0.50 ac)
Primary single-family residential district; 'Single-family dwelling with or without an ADU' is permitted by right (Use table, Art IV). Min lot 21,780 sq ft (1/2 acre) flat for all development (no utility/soil tiering); 5 acres only for raising/keeping animals as an…
- Front
- 35 ft
- Side
- 20 ft
- Rear
- 20 ft
- Max coverage
- 25% impervious
- Min lot
- 21,780 sf (~0.50 ac)
Min lot 21,780 sq ft (1/2 acre) for a single-family dwelling with or without an ADU, or a two-family unit; multi-family dwellings require 1 acre (43,560 sq ft); 5 acres only for keeping animals. Lot Coverage max 25% impervious.
- Front
- 35 ft
- Side
- 20 ft
- Rear
- 20 ft
- Max coverage
- 25% impervious
- Min lot
- 21,780 sf (~0.50 ac)
Mixed-use village district that also permits 'Single-family dwelling with or without an ADU' by right. Min lot 21,780 sq ft (1/2 acre) for single-family (with/without ADU) or two-family; 5 acres only for keeping animals; no minimum for other agricultural uses.
- Front
- 25 ft
- Side
- 20 ft
- Rear
- 20 ft
- Max coverage
- —
- Min lot
- —
Civic/institutional district. No minimum lot size for any development other than the 5-acre floor for keeping animals as an agricultural use. Lot Coverage: 'Not applicable' (no numeric coverage cap); instead a minimum of 50% of any lot shall be open space.
- Front
- 25 ft
- Side
- 20 ft
- Rear
- 20 ft
- Max coverage
- —
- Min lot
- —
Recreation district. No minimum lot size for any development other than the 5-acre floor for keeping animals. Lot Coverage 'Not applicable'; a minimum of 50% of any lot shall be open space. Front setback 25 ft from the right-of-way (from traveled way on Boulder Way, Stone…
- Front
- 20 ft
- Side
- 10 ft
- Rear
- 10 ft
- Max coverage
- —
- Min lot
- —
Open-space / greenbelt district. No minimum lot size for any development other than the 5-acre floor for keeping animals. Lot Coverage 'Not applicable'; a minimum of 95% of any lot shall be open space (effectively no residential building potential).
- Front
- —
- Side
- —
- Rear
- —
- Max coverage
- —
- Min lot
- —
Federal district: those areas of Waterville Valley controlled by the Federal Government and designated as the White Mountain National Forest.
- Front
- 10 ft
- Side
- 10 ft
- Rear
- 10 ft
- Max coverage
- —
- Min lot
- —
Commercial district. No minimum lot size for any development other than the 5-acre floor for keeping animals. Lot Coverage 'Not Applicable'; instead the minimum open space for all uses is one-fifth (20%).
- Front
- 25 ft
- Side
- 20 ft
- Rear
- 20 ft
- Max coverage
- —
- Min lot
- —
Special zoning area on the flat lot at the base of Snow's Mountain (the ski hill itself is excluded). No minimum lot size for any development other than the 5-acre floor for keeping animals. Lot Coverage 'Not applicable'; a minimum of 50% of any lot shall be open space.
Form-based and downtown districts may use build-to lines instead of fixed setbacks (shown as “—”); verify your parcel's district before you build.
Waterville Valley 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 Waterville Valley (Grafton County). A detached ADU can be up to 950 sf.
In Waterville Valley's LDR zone, ADUs follow the single-family setbacks: 35 ft front, 20 ft side, and 20 ft rear. Waterville Valley has 9 zoning districts in total — see the full table below. Confirm your exact zone with the town.

