ADU Construction in Cambridge MA — In-Law Suites, Garage Conversions & More
Boston Smart Plastering builds accessory dwelling units throughout Cambridge, MA. Cambridge is a world-renowned urban city directly across the Charles River from Boston — home to Harvard and MIT, a dense mix of historic neighborhoods, and one of the most dynamic renovation markets in New England. Boston Smart Plastering serves Cambridge homeowners, landlords, and property managers across all trades with expertise in the city's unique older housing stock. Whether you want a basement apartment, garage conversion, attached in-law suite, or detached backyard cottage, we manage every phase from permits to final finishes.
professional
ADU Construction
Services
ADUs are one of the smartest investments Cambridge homeowners can make. Cambridge's housing stock is dominated by 19th and early 20th century multi-family properties, brownstones, and historic single-family homes throughout neighborhoods like Cambridgeport, Inman Square, and North Cambridge. These older properties require specialized plastering skills, careful drywall work around historic details, and experienced crews who understand historic renovation. Under Massachusetts ADU law, most single-family properties in Middlesex County can now add an ADU by-right. Boston Smart Plastering handles the full build — design, permitting, construction, and Certificate of Occupancy. Cambridge sits directly north of Boston across the Charles River — just 3 miles from Downtown — making it one of our most accessible and frequently served communities.
Frequently asked questions
How much does it cost to build an ADU in Cambridge MA?
ADU costs in Cambridge vary by type. A basement conversion typically runs $80,000–$150,000. A detached cottage can cost $180,000–$350,000+. We provide a detailed estimate after visiting your Cambridge property.
Do I need a permit for an ADU in Cambridge MA?
Yes — all ADU construction requires building permits. Under the 2024 Massachusetts ADU law, most Cambridge properties can add an ADU by-right. We handle all permit applications for Middlesex County on your behalf.