Build an ADU in Bow.
New Hampshire's HB 577 lets you add one accessory dwelling unit on your single-family lot in Bow — by-right. A detached ADU can be up to 950 sf, and ADU setbacks match your lot's single-family setbacks.
14 districts
Each district's single-family setbacks — which your ADU follows. The primary residential district is highlighted.
Verified against the official Bow zoning ordinance · source · 2026-07-06
- Front
- 35 ft
- Side
- 20 ft
- Rear
- 20 ft
- Max coverage
- 30% impervious
- Min lot
- 87,120 sf (~2.00 ac)
Primary single-family district (2.0 acres). Front/rear/side measured from the respective lot line (not centerline). Coverage per 6.04 = structures + impervious surfaces as % of total lot area.
- Front
- 35 ft
- Side
- 20 ft
- Rear
- 20 ft
- Max coverage
- 30% impervious
- Min lot
- 87,120 sf (~2.00 ac)
2.0 acres. Low-density residential where municipal sewer is not available/anticipated. Coverage = structures + impervious as % of total lot area.
- Front
- 35 ft
- Side
- 20 ft
- Rear
- 20 ft
- Max coverage
- 30% impervious
- Min lot
- 87,120 sf (~2.00 ac)
2.0 acres. Low-density residential where sewer is available or anticipated.
- Front
- 35 ft
- Side
- 20 ft
- Rear
- 20 ft
- Max coverage
- 80% impervious
- Min lot
- 87,120 sf (~2.00 ac)
Commercial (C) district, footnote-1 tier = served by private well and septic; min lot 2.0 acres. Coverage 80% (structures + impervious as % of total lot area).
- Front
- 35 ft
- Side
- 20 ft
- Rear
- 20 ft
- Max coverage
- 80% impervious
- Min lot
- 43,560 sf (~1.00 ac)
Commercial (C) district, footnote-2 tier = public water OR public sewer; min lot 1.0 acre.
- Front
- 35 ft
- Side
- 20 ft
- Rear
- 20 ft
- Max coverage
- 80% impervious
- Min lot
- 21,780 sf (~0.50 ac)
Commercial (C) district, footnote-3 tier = both public water and public sewer; min lot 0.5 acre (1/2).
- Front
- 50 ft
- Side
- 30 ft
- Rear
- 30 ft
- Max coverage
- 80% impervious
- Min lot
- 217,800 sf (~5.00 ac)
Limited Industrial (I-1), footnote-1 tier = private well and septic; min lot 5.0 acres.
- Front
- 50 ft
- Side
- 30 ft
- Rear
- 30 ft
- Max coverage
- 80% impervious
- Min lot
- 130,680 sf (~3.00 ac)
Limited Industrial (I-1), footnote-2 tier; min lot 3.0 acres.
- Front
- 50 ft
- Side
- 30 ft
- Rear
- 30 ft
- Max coverage
- 80% impervious
- Min lot
- 87,120 sf (~2.00 ac)
Limited Industrial (I-1), footnote-3 tier; min lot 2.0 acres.
- Front
- 50 ft
- Side
- 30 ft
- Rear
- 30 ft
- Max coverage
- 80% impervious
- Min lot
- 87,120 sf (~2.00 ac)
General Industrial (I-2), footnote-1 tier = private well and septic; min lot 2.0 acres.
- Front
- 50 ft
- Side
- 30 ft
- Rear
- 30 ft
- Max coverage
- 80% impervious
- Min lot
- 43,560 sf (~1.00 ac)
General Industrial (I-2), footnote-2 tier; min lot 1.0 acre.
- Front
- 50 ft
- Side
- 30 ft
- Rear
- 30 ft
- Max coverage
- 80% impervious
- Min lot
- 21,780 sf (~0.50 ac)
General Industrial (I-2), footnote-3 tier; min lot 0.5 acre (1/2).
- Front
- 35 ft
- Side
- 20 ft
- Rear
- 20 ft
- Max coverage
- 60% impervious
- Min lot
- 43,560 sf (~1.00 ac)
Civic (town-center) district; min lot 1.0 acre.
- Front
- —
- Side
- —
- Rear
- —
- Max coverage
- 80% impervious
- Min lot
- 87,120 sf (~2.00 ac)
Article 15, Figure 15-1 (rev. Values shown are for the least-restrictive baseline row (Local Roads with municipal water & sewer): min lot 2.0 acres, min frontage 100 ft, max building height 55 ft, max impervious coverage 80% of gross lot area.
Form-based and downtown districts may use build-to lines instead of fixed setbacks (shown as “—”); verify your parcel's district before you build.
Bow 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 Bow (Merrimack County). A detached ADU can be up to 950 sf.
In Bow's R-1 zone, ADUs follow the single-family setbacks: 35 ft front, 20 ft side, and 20 ft rear. Bow has 14 zoning districts in total — see the full table below. Confirm your exact zone with the town.