ADU Contractors near Boston, MA
Pro's Edge Small Homes
27 Pillsbury Street, Georgetown, MA 01833
29.5 miles
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 evaluation.
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New England Outdoor
37 Oakland Avenue, Methuen, MA 01844
29.2 miles
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 guidance.
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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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Mass ADU
144 Arlington Road, Woburn, MA 01801
11.6 miles
Mass ADU is a Massachusetts-based ADU contractor offering full-service accessory dwelling unit construction. Services include free consultations, permitting, design, and build. They serve homeowners statewide with a clear 3-step process.
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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 Massachusetts ADU regulations.
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BlackDog Builders
7 Red Roof Lane, Salem, NH 03079
34.5 miles
BlackDog Builders offers full-service ADU design/build solutions, handling design, permitting, and construction under one roof. Specializing in detached ADUs, backyard cottages, in-law suites, and granny flats, they back projects with a 3-year warranty.
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Amex Construction
15 Industrial Way, Hanover, MA 02339
18.3 miles
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 contract.
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Mass Tiny Homes
800 Lexington Waltham Plaza #1012, Waltham, MA 02451
8.8 miles
Mass Tiny Homes helps you build the perfect ADU for your needs, whether it be for aging parents or rental income, with an easy, streamlined process from start to finish.
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MBA Builders
500 Edgewater Drive, Wakefield, MA 01880
14.2 miles
Massachusetts ADUs are now legal by right statewide after 2024 legislation. MBA Builders offers full-service ADU construction across Greater Boston, with structured preconstruction planning and builds starting around $450/sq ft.
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John Crowley Construction Co
171 Mattakeesett St, Pembroke, MA 02359
22.2 miles
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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WR Builders Inc
397 Elliot Street, Newton, MA 02464
7.3 miles
Atlantic Property Development
444 Broadway Unit B #1069, Saugus, MA 01906
10.9 miles
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.
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Salas Construction
60 Wheaton Avenue, Warwick, RI 27596
44.6 miles
Salas Construction builds custom ADUs in Rhode Island, including attached, detached, and garage conversions. Projects range from $200K–$500K and take 6–12 months. Uses include rentals, guest suites, and multigenerational living.
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Top Pro Inc.
35 Bradshaw Street, Medford, MA 02155
6.6 miles
Top-Pro Construction, Inc. is Greater Boston's trusted ADU builder with 25 years of experience. Specializing in detached ADUs, attached units, garage conversions & basement ADUs to boost property value and rental income.
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MassDwell Solutions
109 Highland Ave, Suite 203, Needham, MA 02494
6.9 miles
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 installation.
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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.