ADU Contractors near Boston, MA
G.M. Roth Design Remodeling
12 Murphy Drive, Nashua, NH 03062
35.5 miles
G.M. Roth Design Remodeling offers full-service ADU construction in southern NH and northeastern MA. With 40+ years of experience, they handle zoning, design, permitting, and build. CAPS-certified, serving Nashua, Manchester, Chelmsford & more... read more
BuildX - Your Building & ADU Experts
24 Rockland Street, Hanover, MA 02339
19.2 miles
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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Platt Builders
109 Central Avenue, Ayer, MA 01432
29.9 miles
Platt Builders is a home remodeling company offering kitchen, bathroom, and whole-home renovations. They focus on custom design, quality craftsmanship, and clear communication, managing every project from planning to completion.
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Boston Construct
1660 Soldiers Field Road, Boston, MA 02135
4.4 miles
Boston Construct is a full-service ADU contractor in Boston, MA, building basement conversions, garage conversions, detached backyard cottages, and in-law suites. They handle design, permitting, and construction for 1-3 family homeowners across Gr... read more
Heritage Modular Homes
16 Harrington Avenue, Shrewsbury, MA 01545
33.8 miles
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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Sordan Construction
809 Turnpike Street, North Andover, MA 01845
24.8 miles
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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ADU Building Systems, LLC
Norwell, MA 02061
17.9 miles
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
True Measure Construction
293 Turnpike Road, Westborough, MA 01581
29 miles
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.
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ADU-PRO Corp.
121 Orchard Street, Millis, MA 02054
18.8 miles
ADU-PRO Corp is a Massachusetts ADU specialist offering full-service construction, permitting, and project management. Led by licensed experts, they help homeowners build granny flats, in-law suites, and backyard cottages up to 900 sq ft.
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JFC Pros Construction
292 Main Street, Northborough, MA 01532
27.4 miles
JFC Pros Construction is a licensed general contractor in Massachusetts offering design, commercial, and new construction services. Their team includes architects, engineers, and tradespeople ensuring full code compliance with NFPA, ADA, IBC, IRC,... read more
Boston Deck Builders
Natick, MA
13.6 miles
Boston Deck Builders offers ADU construction in Greater Boston, including detached, attached, and interior units. Services cover planning, permitting, and build. Costs range from $150K–$400K+. Prefab options available. Compliant with Massachuset... read more
NorthEast Design + Build
2949 Hartford Avenue, Johnston, RI 02919
41.5 miles
NorthEast Design + Build offers ADU and in-law apartment construction across Massachusetts & Rhode Island. Services include detached backyard cottages, in-law suites, and attached additions. Serving Milford, Providence, Warwick & more.
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DiStefano Brothers Construction
433 Main Street, Wakefield, RI 02879
30.7 miles
DiStefano Brothers Construction builds ADUs in Rhode Island, including internal, attached, and detached units. They navigate RI regulations: by-right approval, size limits, occupancy rules, and long-term rental requirements for compliant accessory... read more
Rockhouse Construction
22 Morgan Mill Road, Johnston, RI 02919
38 miles
Rockhouse Construction builds ADUs across Rhode Island, including Providence, Warwick, and Cranston. Options include detached, attached, garage, and basement conversions. Costs range from $60,000 to $480,000+, varying by size and finish level.
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Ron Morgan Construction
8 Harbor rd HB, Mattapoisett, MA 02739
49.2 miles
Ron Morgan Construction is a Massachusetts ADU contractor offering full-service accessory dwelling units from 300–900 sq ft. Licensed under the 2024 Affordable Homes Act, they handle design, permits & construction. ADUs start at $90,000.
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Other cities in Massachusetts
What you need to know
Building ADUs in Boston's Historic Urban Landscape
Boston, Massachusetts is one of America's oldest cities, featuring a dense urban fabric of historic brownstones, triple-deckers, and century-old neighborhoods. This unique character makes working with experienced ADU contractors in Boston absolutely essential. The city's aging housing stock, narrow lot lines, and strict historic preservation requirements create a complex environment that demands specialized knowledge from any contractor tackling an Accessory Dwelling Unit (ADU) project.
Boston's ADU Regulations and Zoning Requirements
In 2021, Boston significantly expanded its ADU program through the Additional Dwelling Unit Program, allowing owner-occupants in all Boston neighborhoods to add one ADU to their property. This was a major policy shift that opened up new opportunities for homeowners. Key regulatory points that qualified ADU contractors in Boston, MA must navigate include:
- The property owner must occupy either the primary unit or the ADU as their principal residence
- ADUs must comply with the Boston Zoning Code and the State Building Code (780 CMR)
- Maximum ADU size is generally limited to 900 square feet or the size of the primary unit, whichever is smaller
- Projects in historic districts require additional approval from the Boston Landmarks Commission
- Parking requirements may apply depending on the specific neighborhood and zoning district
- All ADU projects require permits through the Inspectional Services Department (ISD)
Types of ADUs Boston Contractors Commonly Build
Given Boston's dense residential neighborhoods, the most common ADU types differ from those seen in suburban or western U.S. cities. Skilled Boston ADU contractors frequently work on:
- Basement ADUs – Converting existing basement space in brownstones and triple-deckers
- Attic conversions – Transforming underutilized attic space into livable units
- Interior unit conversions – Reconfiguring existing floor plans within multi-family homes
- Detached backyard cottages – Where lot size and zoning permit
Why Hiring a Local Boston ADU Contractor Matters
Hiring a contractor with deep local expertise is critical in Boston. Local ADU contractors understand the nuances of working with Boston's aging infrastructure, including outdated electrical panels, cast-iron plumbing, and older foundation systems common in neighborhoods like Jamaica Plain, South Boston, Dorchester, and Roxbury. They also maintain established relationships with the city's permitting offices, helping to streamline approvals and avoid costly delays.
Cost of Building an ADU in Boston
Due to high labor costs and the complexity of urban construction, ADU construction costs in Boston typically range from $150,000 to $350,000 or more, depending on the scope and type of project. Basement conversions tend to be more affordable, while detached units or projects in historic districts can cost significantly more. Working with a reputable Boston ADU contractor ensures your investment is protected and your project meets all local code requirements.