Tiny Homes: Cambridge vs Somerville
How do tiny homes rules compare between Cambridge, MA and Somerville, MA?
Cambridge has fewer restrictions than Somerville.
Cambridge, MA
Middlesex County
Tiny homes on foundations are allowed as ADUs in Cambridge under MGL c.40A s.3A. Tiny homes on wheels are treated as recreational vehicles and cannot be used as permanent dwellings under the MA State Building Code.
View full Cambridge rules →Somerville, MA
Middlesex County
Tiny homes on foundations can qualify as ADUs in Somerville under the 2024 Affordable Homes Act. Tiny homes on wheels are treated as RVs and generally cannot be used as permanent dwellings.
View full Somerville rules →Key Facts Comparison
| Fact | Cambridge | Somerville |
|---|---|---|
| Tiny home on foundation | Allowed as ADU | - |
| Max ADU size | 900 sq ft | - |
| Tiny home on wheels | Not allowed as dwelling | - |
| Governing code | 780 CMR and c.40A s.3A | - |
| Park model units | Not permitted in Cambridge | - |
| Foundation tiny home | - | Allowed as ADU |
| State code | - | 780 CMR Appendix AQ |
| Max as ADU | - | 900 sq ft |
| Tiny homes on wheels | - | Not permanent dwelling |
| RV residency | - | Prohibited long-term |
Highlighted rows indicate differences between cities.
Cambridge FAQ
Can I park a tiny house on wheels in my Cambridge driveway?
Not as a dwelling. THOWs are treated as RVs and cannot be used for long-term living under state code.
Can I build a 600 sq ft tiny home as an ADU?
Yes, with a foundation and full building permit it qualifies under the state ADU law.
Somerville FAQ
Can I live in a tiny home in Somerville?
Yes on a permanent foundation as an ADU. Tiny homes on wheels cannot be permanent dwellings.
Is there a minimum size?
Appendix AQ allows dwellings as small as 120 sq ft if code compliant; Somerville follows state code.
Compare other topics
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