Detached ADU near Leominster, MA

Rare Forms & New Frameworks offer the Casita series—prefabricated ADUs built with sustainable Massachusetts wood and straw. All-electric, non-toxic, and customizable, models include the Cabinita 300 and Terra 600 for eco-friendly backyard co... read more

Hawthorn Builders offers end-to-end ADU construction, managing consultation, design, permitting, and building. As a detached ADU and garage conversion contractor, they complete accessory dwelling units in ~90 days with minimal disruption.

Top Notch Contracting is a Massachusetts ADU builder specializing in detached backyard cottages, garage conversions, in-law suites, and multigenerational spaces. They manage permitting, construction, and completion across Boston and MA.

ADU Building Systems LLC builds factory & site-built ADUs in Massachusetts, including detached, attached & converted units. Offering 10-year structural warranties, cost savings up to 50%, and full-service design to turnkey construction.read more

Stella Home Services is a Greater Boston ADU contractor specializing in basement apartments, garage conversions, in-law suites & home additions. They manage design, permitting & construction for fully functional accessory dwelling units.read more

Avalon Building Systems builds custom modular homes and ADUs across the northeastern US. A VA Certified Builder, they offer turnkey services, Energy Star-compliant construction, and compact floor plans like in-law suites and backyard cottages.

Heritage Modular Homes builds ADUs across MA, RI, CT & NH. With 40+ years experience, they offer custom ADU design, modular installation & in-law suites, backed by a 10-year warranty & free consultations.

New England Outdoor, a family-owned business in Methuen, MA, builds custom sheds, garages, pavilions, and ADUs across New England. Specializing in ADU construction, garage conversions, and in-law suites, they handle design, permits, and zoning gui... read more

Massachusetts homeowners can get permit-ready ADU plans starting at $800, delivered in days. Three tiers cover plans, cost estimates, and full custom design up to $3,100. Free ADU Starter Guide available.

ADUs are now legal statewide in Massachusetts. Atlantic Property Development builds custom Accessory Dwelling Units on the North Shore, offering design, permitting, and construction services for detached, attached, and garage conversion ADUs.

Expert ADU builders serving Massachusetts homeowners. Services include detached ADUs, garage conversions, basement units & in-law suites. Fully permitted, code-compliant builds. Costs from $80K. Serving Boston, Cambridge, Worcester & state... read more

True Measure Construction, a Westborough, MA general contractor, specializes in full-service ADU construction—covering permits, site prep, and finishing—plus kitchen and bathroom remodeling for a complete home improvement solution.

Pro's Edge Small Homes is a licensed ADU contractor in MA & NH with 20+ years experience. They offer turnkey design, permitting & modular construction of granny flats, in-law suites & backyard cottages, including a free property evalua... read more

Regulus Construction is a licensed ADU contractor serving MetroWest Massachusetts. They build detached backyard cottages, garage conversions, and in-law suites, managing design, permitting, and construction across 40+ towns.