Room Addition Permit Requirements in Cambridge, MA
Cambridge is a city of 118,403 residents in Massachusetts that follows the 2015 building code. Whether you need a building permit for your Room Addition project depends on the scope of work — here's what Cambridge's building department requires.
When you DO need a permit
All additions require building and zoning permits in Cambridge, MA.
Estimated fee: $520 – $1,560
Typical timeline: About 4 weeks
Source: Massachusetts State Building Code (780 CMR)
Large additions require comprehensive permitting in Cambridge, MA.
Estimated fee: $1,040 – $5,200
Typical timeline: About 6 weeks
Source: Massachusetts State Building Code (780 CMR)
Two-story additions require comprehensive permitting in Cambridge, MA.
Estimated fee: $1,300 – $6,500
Typical timeline: About 6 weeks
Source: Massachusetts State Building Code (780 CMR)
Room additions typically require zoning review for setbacks, height limits, and lot coverage. Your addition must comply with your zoning district's building envelope requirements.
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Frequently Asked Questions
Estimated permit fees for Room Addition projects in Cambridge, MA range from $520 – $1,560. Fees vary based on project scope and valuation.
It depends on the specifics of your project. Some smaller Room Addition projects may be exempt from permit requirements, while larger ones typically require a permit. Use our free lookup tool to check your specific situation.
Working without a required permit in Cambridge can result in fines, stop-work orders, being required to remove completed work, and complications when selling your home. It's always best to check first.
Typical approval time for Room Addition permits in Cambridge is About 4 weeks. More complex projects may take longer if plan review is required.
Learn More About Room Addition Permits
Read our complete guide covering permit requirements, costs, common exemptions, and the application process.
Read Room Addition Guide →