ADU Rules: Attleboro vs Somerset
How do adu rules rules compare between Attleboro, MA and Somerset, MA?
Attleboro and Somerset have similar restriction levels.
Attleboro, MA
Bristol County
Under Massachusetts law (Ch. 358 of Acts of 2024, effective Feb 2025), ADUs under 900 sq ft are allowed by right on single-family lots statewide, including Attleboro. ADUs must have a separate entrance and cannot exceed 900 sq ft or half the principal dwelling area. Both attached and detached ADUs are permitted.
View full Attleboro rules →Somerset, MA
Bristol County
Under Massachusetts law (Ch. 358 of Acts of 2024, effective Feb 2025), ADUs under 900 sq ft are allowed by right on single-family lots in all Bristol County municipalities. Towns cannot prohibit ADUs or impose owner-occupancy requirements. Both attached and detached ADUs are permitted under the state framework.
View full Somerset rules →Key Facts Comparison
| Fact | Attleboro | Somerset |
|---|---|---|
| State Law | Ch. 358 Acts of 2024 — by right | Ch. 358 Acts of 2024 — by right |
| Max Size | 900 sq ft or 50% of principal dwelling | 900 sq ft or 50% of principal dwelling |
| Types | Attached, internal, or detached | - |
| Owner Occupancy | Cannot be required by municipality | Cannot be required |
| Applies Countywide | - | All municipalities must allow |
Highlighted rows indicate differences between cities.
Attleboro FAQ
Can I build an ADU on my property in Attleboro?
Under Massachusetts law (Ch. 358 of Acts of 2024, effective Feb 2025), ADUs under 900 sq ft are allowed by right on single-family lots statewide, including Attleboro. ADUs must have a separate entrance and cannot exceed 900 sq ft or half the principal dwelling area. Both attached and detached...
What are the size limits for an accessory dwelling unit in Attleboro?
State Law: Ch. 358 Acts of 2024 — by right. Max Size: 900 sq ft or 50% of principal dwelling. Types: Attached, internal, or detached. Owner Occupancy: Cannot be required by municipality.
Somerset FAQ
Can I build an ADU on my property in Bristol County?
Under Massachusetts law (Ch. 358 of Acts of 2024, effective Feb 2025), ADUs under 900 sq ft are allowed by right on single-family lots in all Bristol County municipalities. Towns cannot prohibit ADUs or impose owner-occupancy requirements. Both attached and detached ADUs are permitted under the...
What are the size limits for an accessory dwelling unit in Bristol County?
State Law: Ch. 358 Acts of 2024 — by right. Max Size: 900 sq ft or 50% of principal dwelling. Applies Countywide: All municipalities must allow. Owner Occupancy: Cannot be required.
Compare other topics
See how Attleboro and Somerset compare on other ordinance categories.
Want to add a third city?
Use our full comparison tool to compare up to three cities.
Open Comparison Tool