Occupancy Limits: Ayer vs Somerville
How do occupancy limits rules compare between Ayer, MA and Somerville, MA?
Somerville has fewer restrictions than Ayer.
Ayer, MA
Middlesex County
Middlesex County STRs must comply with State Building Code 780 CMR occupancy standards and local bylaws, typically limiting occupancy to two people per bedroom plus two, with lodging-house rules for 4+ unrelated.
View full Ayer rules →Somerville, MA
Middlesex County
Somerville STR occupancy follows MA Sanitary Code 105 CMR 410 room-size standards, typically allowing two guests per bedroom plus additional occupants based on square footage.
View full Somerville rules →Key Facts Comparison
| Fact | Ayer | Somerville |
|---|---|---|
| Typical formula | 2 per bedroom plus 2 | - |
| Sanitary code | 105 CMR 410 | - |
| Building code | 780 CMR | - |
| Lodging threshold | 4+ unrelated persons | - |
| Typical cap | 10 to 12 per unit | - |
| State Code | - | 105 CMR 410 minimums |
| Rule of Thumb | - | 2 guests per bedroom |
| First Occupant | - | 150 sq ft living space |
| Each Additional | - | 100 sq ft |
| Contact | - | Somerville 311 or (617) 625-6600 |
Highlighted rows indicate differences between cities.
Ayer FAQ
How many guests can stay in a Middlesex County STR?
Most towns use a formula of 2 per bedroom plus 2, capped at 10 to 12 total. Sanitary code requires 70 sq ft for the first occupant and 50 sq ft per additional.
What triggers lodging house rules?
Renting to four or more unrelated persons under MGL c.140 s.22 may require a lodging house license, which has far more stringent safety and zoning requirements than a standard STR.
Somerville FAQ
Can I list my 2-bedroom Somerville condo for 6 guests?
Only if the total square footage supports it under 105 CMR 410 and egress is adequate. Most 2-bedroom condos realistically support 4 guests. Inspectional Services can confirm your specific unit.
Do infants count toward occupancy?
Under 105 CMR 410, children under one year old generally do not count, but older children do. Check with ISD for your specific situation.
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