Somerville
Middlesex County · Pop. 81,045
Somerville has approved 24 of 40 ADU applications (60% approval rate) and has 5 of 8 bylaw provisions consistent with state law.
Based on 24 approved ADU applications and 81,045 residents
Permits
40 applications since the ADU law took effect in Feb 2025
Bylaw Consistency
Somerville is relatively ADU-friendly after adopting Ord. 2025-16. The ‘Backyard Cottage’ building type makes detached ADUs straightforward. The main watch item is the affordability requirement in Neighborhood Residential zones — it adds compliance costs that may discourage some projects.
Provision-by-provision analysis available
We've mapped 8 provisions in Somerville against Chapter 150. See which specific bylaw sections appear inconsistent with state law.
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No cost data available yet for Somerville.
Try the cost estimatorADU Impact on Housing Production
In 2024, Somerville issued 83 total residential building permits. In the first year of the ADU law, 24 ADU permits were approved — equivalent to 28.9% of prior-year housing production.
Source: Census Bureau (2024) via UMass Donahue Institute; EOHLC ADU Survey (2025)
How Somerville Compares
Next Steps
Sources: EOHLC ADU Survey 2025. Population estimates from 2024 Census ACS.
Disclaimer: ADU Pulse provides data for informational purposes only. It does not constitute legal, financial, or construction advice.Bylaw consistency analysis reflects our interpretation of public records and may not reflect the most current local amendments.
See methodology for details on data collection, scoring, and consistency analysis.