Build an ADU in Tilton.
New Hampshire's HB 577 lets you add one accessory dwelling unit on your single-family lot in Tilton — 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 Tilton zoning ordinance · source · 2026-07-06
- Front
- 20 ft
- Side
- 20 ft
- Rear
- 20 ft
- Max coverage
- 50% impervious
- Min lot
- 43,560 sf (~1.00 ac)
Designed for single-family dwelling units (Art IV). Min lot 1 acre w/ sewer AND 2 acres w/o sewer; backland lot 2 acres. Value shown is w/ sewer (1 acre = 43,560 sf); w/o sewer = 87,120 sf. Min frontage 100 ft w/ municipal sewer / 200 ft w/o (Note 3).
- Front
- 20 ft
- Side
- 20 ft
- Rear
- 20 ft
- Max coverage
- 60% impervious
- Min lot
- 15,000 sf (~0.34 ac)
Accommodates single and multi-family dwelling units in developed areas with water and sewer (Art IV). Min lot 15,000 sf w/ sewer AND 30,000 sf w/o sewer; backland 60,000 sf. Value shown is w/ sewer. Min frontage 100 ft Max height 35 ft Base residential density 2 dwelling…
- Front
- 20 ft
- Side
- 20 ft
- Rear
- 20 ft
- Max coverage
- 50% impervious
- Min lot
- 20,000 sf (~0.46 ac)
Accommodates single and two-family dwellings plus small-scale retail/service along Routes 3/11 (Art IV). Min lot 20,000 sf w/ sewer AND 1 acre (43,560 sf) w/o sewer; backland 2 acres. Value shown is w/ sewer.
- Front
- 40 ft
- Side
- 40 ft
- Rear
- 40 ft
- Max coverage
- 40% impervious
- Min lot
- 130,680 sf (~3.00 ac)
Single-family plus wide range of agricultural uses where no utilities exist/planned (Art IV). Min lot 3 acres (130,680 sf) both w/ and w/o sewer; backland 6 acres. Min frontage 250 ft Max height 60 ft Base residential density 1 dwelling unit per lot.
- Front
- —
- Side
- —
- Rear
- —
- Max coverage
- 100% impervious
- Min lot
- 30,000 sf (~0.69 ac)
Wide range of office/retail/service plus high-density residential in historic downtown (Art IV; listed as 'ON' in text due to OCR, 'DN' in table). No lot size w/ sewer (n/a); 30,000 sf w/o sewer; backland 60,000 sf.
- Front
- 30 ft
- Side
- 20 ft
- Rear
- 20 ft
- Max coverage
- 60% impervious
- Min lot
- 43,560 sf (~1.00 ac)
Recreation/restaurant/accommodations plus small-scale retail along Routes 3/11 near Silver and Winnisquam Lakes (Art IV). Min lot 1 acre (43,560 sf) both w/ and w/o sewer; backland 2 acres. Min frontage 150 ft Max height 40 ft Base residential density 1 dwelling unit per lot.
- Front
- 30 ft
- Side
- 50 ft
- Rear
- 20 ft
- Max coverage
- 75% impervious
- Min lot
- 43,560 sf (~1.00 ac)
Large-scale retail/service, restaurants, accommodations at highway interchange (Art IV). Min lot 1 acre (43,560 sf) both w/ and w/o sewer; backland 2 acres. Min frontage 0.
- Front
- 30 ft
- Side
- 20 ft
- Rear
- 20 ft
- Max coverage
- 75% impervious
- Min lot
- 20,000 sf (~0.46 ac)
Wide range of commercial uses along arterial highway (Art IV). Min lot 20,000 sf w/ sewer AND 1 acre (43,560 sf) w/o sewer; backland 2 acres. Value shown is w/ sewer. Min frontage 100 ft w/ municipal sewer / 200 ft w/o (Note 3).
- Front
- 30 ft
- Side
- 20 ft
- Rear
- 20 ft
- Max coverage
- 75% impervious
- Min lot
- 43,560 sf (~1.00 ac)
Manufacturing, warehousing, and office uses (Art IV). Min lot 1 acre (43,560 sf) w/ sewer AND 2 acres w/o sewer; backland 4 acres. Value shown is w/ sewer. Min frontage 0.
Form-based and downtown districts may use build-to lines instead of fixed setbacks (shown as “—”); verify your parcel's district before you build.
Tilton 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 Tilton (Belknap County). A detached ADU can be up to 950 sf.
In Tilton's MR zone, ADUs follow the single-family setbacks: 20 ft front, 20 ft side, and 20 ft rear. Tilton has 9 zoning districts in total — see the full table below. Confirm your exact zone with the town.