ADU Contractors in Massachusetts
Alcantara Construction
407R Mystic Avenue, Medford, MA 02155
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 efficiently.
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WR Builders Inc
397 Elliot Street, Newton, MA 02464
John Crowley Construction Co
171 Mattakeesett St, Pembroke, MA 02359
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.
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Honorato Company
34 Commerce Way, Woburn, MA 01801
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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Sordan Construction
809 Turnpike Street, North Andover, MA 01845
Planning an ADU in Massachusetts? Costs range from $250–$500+ per sq ft. State law now allows ADUs by right on single-family lots. Learn about permits, the Stretch Energy Code, and working with a qualified ADU contractor in Greater Boston.
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South Coast & Associates Inc
45 Slocum Road, Dartmouth, MA 02747
South Coast & Associates builds custom ADUs in Southeastern Massachusetts. From detached backyard cottages to garage conversions and in-law suites, they handle design, permitting, and construction for single-family homeowners.
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All City Remodeling
3 Sophie Rd, Peabody, MA 01960
All City Remodeling Co. offers ADU construction, period molding installation, and beam ceiling paneling in Boston, MA, and North Shore communities including Hamilton, Salem, and Manchester-by-the-Sea.
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Heritage Modular Homes
16 Harrington Avenue, Shrewsbury, MA 01545
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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FiveTen Construction & Design
462 Washington Street, Woburn, MA 01801
FiveTen Construction & Design is a Massachusetts ADU contractor offering design, permitting, and construction services. They build detached, attached, basement, and garage ADUs, ensuring full compliance with MA building codes and zoning regulations.
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Design 1 Kitchen & Bath
363 Great Road, Bedford, MA 01730
Design 1 Kitchen & Bath designs and builds ADUs in Massachusetts, handling consultation, design, permitting, and construction. ADUs add rental income, multigenerational living space, and property value for Greater Boston homeowners.
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Top Notch Contracting
13 A Street, Burlington, MA 01803
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.
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Trust Contractors
65 Hancock Street, Bedford, MA 01730
Trust Contractors designs and builds ADUs, including detached units, garage conversions, basement ADUs, and in-law suites. Services cover zoning, permits, and construction, helping homeowners add rental income, family housing, or flexible living space.
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BuildX - Your Building & ADU Experts
24 Rockland Street, Hanover, MA 02339
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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Woodland Builders
195 Hanover Street, Hanover, MA 02339
Woodland Builders is a full-service ADU builder serving South Shore, MA, including Hingham, Plymouth & Scituate. They manage design through construction, ensuring quality, compliance, and streamlined project management for accessory dwelling units.
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Boston ADU Builder
807 Massachusetts Avenue, Boston, MA 02118
Boston ADUs add rental income ($1,500–$3,000/month), boost property value, and support multi-generational living. Boston ADU Builder offers detached, attached, garage, and basement conversions, handling design, permits, and construction in 8–12 months.
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Other cities in Massachusetts
What you need to know
ADU Contractors in Massachusetts: Navigating the 2024 Zoning Reform
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.
What Massachusetts ADU Contractors Do
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.
Key Regulations Massachusetts ADU Contractors Must Follow
Even with the statewide by-right allowance, ADU contractors in Massachusetts must still navigate several important regulations, including:
- Size limitations: ADUs must generally not exceed 900 square feet or half the square footage of the primary dwelling, whichever is smaller, under the Affordable Homes Act guidelines.
- Owner-occupancy rules: Municipalities may impose owner-occupancy requirements, though the state has limited how restrictive these can be.
- Setback and lot coverage requirements: Local zoning bylaws still govern setbacks, height limits, and lot coverage, which vary by municipality.
- Utility connections: ADUs must meet Massachusetts plumbing, electrical, and energy codes, including compliance with the Massachusetts Stretch Energy Code in many communities.
- Historic districts: In cities like Boston, Salem, or Nantucket, ADU projects may require additional review from local historic commissions.
Choosing the Right ADU Contractor in Massachusetts
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.
The Value of Building an ADU in Massachusetts
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.