Skip to main content
CityRuleLookup
πŸ—οΈ Accessory Structures/Garage Conversions

Garage Conversions: Cambridge vs Lexington

How do garage conversions rules compare between Cambridge, MA and Lexington, MA?

Cambridge and Lexington have similar restriction levels.

Cambridge, MA

Middlesex County

Some Restrictions

Garage conversions to living space are permitted in Cambridge with full building permits. Under the 2024 MA Affordable Homes Act, converting a garage into an ADU is allowed by right in most zones.

View full Cambridge rules β†’

Lexington, MA

Middlesex County

Some Restrictions

Garage conversions in Middlesex County are subject to local zoning bylaws and the MA State Building Code 780 CMR. Conversion to ADUs is now by-right under the 2024 Affordable Homes Act.

View full Lexington rules β†’

Key Facts Comparison

FactCambridgeLexington
Full building permitRequired-
ADU conversionBy right under state law-
Energy codeMA Specialized Stretch Code-
Parking replacementTypically waived for ADU-
Historic districtsExtra review-
Building Permit-Required (780 CMR)
Ceiling Min-7 feet
ADU Conversion-By-right under s.3A
Parking Replacement-Often required
Historic Review-Certificate of Appropriateness

Highlighted rows indicate differences between cities.

Cambridge FAQ

Can I convert my detached garage into an apartment in Cambridge?

Yes, under the 2024 state ADU law this is generally allowed by right, subject to building code.

Do I have to replace the parking I lose?

Generally no for ADU conversions under MGL c.40A s.3A.

Lexington FAQ

Can I convert my garage to a bedroom or ADU?

Yes with a building permit. ADU conversions are now by-right statewide under the 2024 Affordable Homes Act.

Do I need to replace parking?

Most towns require replacement parking, but ADU conversions have capped parking requirements under state law.

Compare other topics

See how Cambridge and Lexington 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