ADU Construction in Quincy MA — In-Law Suites, Garage Conversions & More
Boston Smart Plastering builds accessory dwelling units throughout Quincy, MA. Quincy is Massachusetts' seventh-largest city, a dense and diverse urban community directly south of Boston with one of the region's most active housing markets. From the triple-deckers of Quincy Center to the waterfront condos of Marina Bay, Boston Smart Plastering has completed hundreds of projects across Quincy's varied neighborhoods. 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 Quincy homeowners can make. Quincy's housing stock spans Victorian-era multi-families in Wollaston and Merrymount, mid-century ranch homes in North Quincy, and newer construction near the waterfront. Older homes frequently need plaster repair, skim coating, and insulation upgrades. The city's dense urban character means exterior work — roofing, siding, and power washing — is in constant demand. Under Massachusetts ADU law, most single-family properties in Norfolk County can now add an ADU by-right. Boston Smart Plastering handles the full build — design, permitting, construction, and Certificate of Occupancy. Quincy sits directly south of Boston — just 8 miles from Downtown — making it one of our most frequently served communities.
Frequently asked questions
How much does it cost to build an ADU in Quincy MA?
ADU costs in Quincy 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 Quincy property.
Do I need a permit for an ADU in Quincy MA?
Yes — all ADU construction requires building permits. Under the 2024 Massachusetts ADU law, most Quincy properties can add an ADU by-right. We handle all permit applications for Norfolk County on your behalf.