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
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.
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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.
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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
Turkel Design offers custom-designed accessory dwelling units (ADUs) using a prefab process. Highlights include expert cabinetry, smart storage, and high-quality finishes, ensuring ADUs feel purposeful and cohesive with the main residence.
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MassDwell Solutions builds modular ADUs for homeowners, investors & developers. Models range from 470–892 sqft, starting at $164,500. Factory-built steel frame units include full warranties, energy-efficient features & 8–12 week instal... read more
BuildX is a premier ADU builder in Southeastern Massachusetts with 40+ years of experience and $450M+ in projects. Offering custom stick-built ADUs, a 100-day build guarantee, and transparent pricing starting from $254,540.
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Alcantara Construction is an experienced ADU contractor specializing in detached ADUs, garage conversions, JADUs, in-law suites, and granny flats. They guide homeowners through planning, permitting, and building accessory dwelling units efficientl... read more
John Crowley Construction Co offers turnkey ADU construction on Massachusetts' South Shore, serving Pembroke, Plymouth, Hingham & more. Licensed (#114197), insured, 25+ years experience. Detached, attached, garage & basement ADUs available... read more
Amex Construction is a Hanover-based design-build ADU contractor serving Massachusetts' South Shore. They manage detached ADUs, barn conversions, and basement suites, handling design, permitting, septic upgrades, and construction under one contrac... read more
Spring Home Improvement offers expert ADU contractor services in Norfolk, MA. Family-owned since 2012, they handle design, permits, and construction with 10+ years of experience, transparent pricing, and a one-year labor warranty.
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Honorato Company offers a structured construction process in Boston, covering ADUs, garage conversions & renovations. From consultation to final walkthrough, they ensure transparency, permitting, design, and clear communication throughout.
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13 Gables Inc, a licensed MA general contractor with 38+ years experience, builds custom ADUs including detached units, garage conversions & in-law suites. Massachusetts' 2025 Affordable Homes Act now allows ADUs by right in single-family zone... read more
Massachusetts made a landmark move in 2024 when Governor Maura Healey signed the Affordable Homes Act, a sweeping housing reform that significantly changed how Accessory Dwelling Units (ADUs) are handled across the state. Under this legislation, ADUs are now allowed by-right in single-family zoning districts statewide, meaning homeowners no longer need special permits or variances in most cases. This makes Massachusetts one of the more progressive states for ADU development, and experienced ADU contractors in Massachusetts are in high demand to help homeowners take advantage of these new opportunities.
ADU contractors in Massachusetts specialize in designing, permitting, and building accessory dwelling units, which can include basement conversions, garage conversions, detached backyard cottages, and attached in-law suites. These professionals are well-versed in the state's building codes, local zoning bylaws, and the specific requirements set by the Massachusetts State Building Code (780 CMR). A qualified ADU contractor will guide homeowners through every stage of the process, from initial design to final inspection.
Even with the statewide by-right allowance, ADU contractors in Massachusetts must still navigate several important regulations, including:
When selecting an ADU contractor in Massachusetts, homeowners should look for professionals who hold a valid Massachusetts Construction Supervisor License (CSL) and carry proper liability and workers' compensation insurance. Experience with local permitting offices is a major advantage, as requirements can differ significantly between cities like Boston, Worcester, Springfield, and Cambridge. Ask for references from completed ADU projects and verify that the contractor is familiar with both state and local regulations.
With one of the highest housing costs in the nation, Massachusetts homeowners have strong financial incentives to build ADUs. A well-constructed ADU can generate rental income, increase property value, and provide housing for aging family members. Working with a knowledgeable ADU contractor ensures your project is completed efficiently, legally, and to the highest standards, making your investment worthwhile for years to come.