Build an ADU in Hampstead.
New Hampshire's HB 577 lets you add one accessory dwelling unit on your single-family lot in Hampstead — by-right. A detached ADU can be up to 950 sf, and ADU setbacks match your lot's single-family setbacks.
8 districts
Each district's single-family setbacks — which your ADU follows. The primary residential district is highlighted.
Verified against the official Hampstead zoning ordinance · source · 2026-07-06
- Front
- 30 ft
- Side
- 30 ft
- Rear
- 50 ft
- Max coverage
- —
- Min lot
- 45,000 sf (~1.03 ac)
PRIMARY single-family residential district (III-2). LOT AREA: minimum 45,000 sf (III-2:4A), BUT the true minimum is SOIL/SLOPE-BASED per Article II-1 and appendix Table 1A (ranges 31,750-132,000 sf by soil group/slope); 45,000 sf is only a not-below floor.
- Front
- 30 ft
- Side
- 30 ft
- Rear
- 50 ft
- Max coverage
- —
- Min lot
- 45,000 sf (~1.03 ac)
Single-family dwellings are the ONLY permitted use (III-3:2.1); commercial and industrial uses prohibited; storage/keeping of commercial vehicles prohibited. LOT AREA: minimum 45,000 sf (III-3:4A), plus the soil/slope-based requirement of Article II-1 / Table 1A (the larger…
- Front
- 30 ft
- Side
- 30 ft
- Rear
- 30 ft
- Max coverage
- 15% building
- Min lot
- —
General retail/service commercial (III-4). LOT AREA (III-4:4A): minimum lot size equals 3/4 of the soil-based minimum required under Article II-1 / Table 1A (unless NHWSPCC subsurface-disposal rules require larger); because that base is itself soil/slope-variable, no single…
- Front
- 30 ft
- Side
- 30 ft
- Rear
- 30 ft
- Max coverage
- 15% building
- Min lot
- 45,000 sf (~1.03 ac)
Heavier commercial than C-1 (automotive service/sales, building-material sales, kennels/nurseries, light manufacturing of instruments/electronics, laboratories, recreation) plus any C-1 use (III-5). LOT AREA (III-5:4A): the soil-based figure under Art II-1/II-2 (Table 1A) OR…
- Front
- 30 ft
- Side
- 15 ft
- Rear
- 15 ft
- Max coverage
- 15% building
- Min lot
- 45,000 sf (~1.03 ac)
Industrial/heaviest commercial (III-6): any C-2 use plus warehouses/storage, manufacturing/fabrication/conversion facilities, laboratories, and (by special exception) toxic-materials processing/storage.
- Front
- —
- Side
- —
- Rear
- —
- Max coverage
- —
- Min lot
- —
Single-purpose district: sanitary landfill ONLY, and only on the specific state-approved site, per NH solid-waste laws (III-7:2).
- Front
- 200 ft
- Side
- 75 ft
- Rear
- 75 ft
- Max coverage
- —
- Min lot
- 10,000 sf (~0.23 ac)
Mobile-home PARKS only; stick-built/on-site homes prohibited (III-8). DIMENSIONS (III-8:4): a Mobile Home Park must have a minimum land area of 10 acres, and each mobile-home SITE a minimum of 10,000 sf (the minLotSqft field records the 10,000 sf per-site figure; the 10-acre…
- Front
- —
- Side
- —
- Rear
- —
- Max coverage
- —
- Min lot
- —
Descriptive/protective historic overlay under RSA 674:46-a (ordinance cites RSA 31:89-l / historic-district authority), NOT a buildable base residential or commercial district.
Form-based and downtown districts may use build-to lines instead of fixed setbacks (shown as “—”); verify your parcel's district before you build.
Hampstead 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 Hampstead (Rockingham County). A detached ADU can be up to 950 sf.
In Hampstead's A zone, ADUs follow the single-family setbacks: 30 ft front, 30 ft side, and 50 ft rear. Hampstead has 8 zoning districts in total — see the full table below. Confirm your exact zone with the town.