MANCHESTER, NEW HAMPSHIRE · HILLSBOROUGH COUNTY
BUILD AN ADU IN MANCHESTER.
✓ Allowed by-right · RSA 674:71-73
New Hampshire's HB 577 lets you add one accessory dwelling unit on your single-family lot in Manchester — by-right. A detached ADU can be up to 950 sf, and ADU setbacks match your lot's single-family setbacks.
Manchester setback reference · R1A zone
- Front setback
- 30 ft
- Side setback
- 12 ft
- Rear setback
- 25 ft
- Max lot coverage
- 30%
- Min lot size
- 10,000 sf (~0.23 ac)
- Max detached ADU
- 950 sf
Figures reflect Manchester's R1A residential zone and are a planning aid — your parcel's exact zone and overlays (wetland, shoreland) are verified before we lock your price.
Confirm your zoning
Manchester ADU FAQ
Can I build an ADU in Manchester, NH?
Yes. Under NH RSA 674:71-73 (HB 577), one accessory dwelling unit is allowed by-right on single-family lots statewide, including Manchester (Hillsborough County). A detached ADU can be up to 950 sf.
What are the ADU setbacks in Manchester?
In Manchester's R1A zone, ADUs follow the single-family setbacks: 30 ft front, 12 ft side, and 25 ft rear. Confirm your exact zone with the town.