ADU Construction

ADU Builders - Massachusetts

ADU Construction Services in Middlesex and Worcester Counties

Baystate Group Difference

Crafting Custom ADUs to Enhance Your Property

We specialize in Accessory Dwelling Unit (ADU) construction, offering Massachusetts homeowners tailored solutions that expand living spaces and enhance property value. With over 30 years of experience, we bring a deep understanding of local building codes, zoning requirements, and architectural styles. Every ADU we build is designed to be both functional and seamlessly integrated with your property.

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What is an Accessory Dwelling Unit (ADU)?

An Accessory Dwelling Unit (ADU) is a self-contained housing unit built on the same property as a primary residence. These secondary units often include their own kitchen, bathroom, and living space, making them fully functional independent homes.


ADUs come in various forms, including:

  • Detached structures in the backyard (e.g., a guest house).
  • Garage conversions.
  • Basement apartments.


ADUs are a smart investment for homeowners looking to maximize their property’s potential. They can serve as:

  • Private living quarters for family members.
  • Rental units to generate steady income.
  • Guest houses for visitors.


As the demand for versatile housing solutions grows, ADUs are becoming increasingly popular throughout Massachusetts.

The Right Choice for Your ADU

Why Choose Us for Your ADU Construction Project

ADU Expertise

We handle every aspect of your ADU project, including design, permits, construction, and final inspections, so you can enjoy a seamless experience from start to finish.

Owner-Involved

Our owner personally oversees each project to ensure every detail meets our high standards and your specific needs.

Tailored Designs

We work closely with you to create an ADU that complements your home and fits your unique vision—whether it’s modern, traditional, or something in between.

Navigating Regulations

ADUs have specific zoning and permitting requirements in Massachusetts. With decades of experience, we streamline

Planning Your ADU

Your Guide to ADU Construction

Working with Baystate Group Builders to create your ADU is a clear, streamlined process. From concept to completion, we handle every step with transparency and professionalism. Here’s how we bring your ADU vision to life:

  • 1. Initial Consultation

    We start with a one-on-one consultation to understand your goals, lifestyle needs, and vision for the ADU. During this stage, we’ll discuss your budget, timeline, and any preliminary ideas, ensuring we have a clear roadmap tailored to your unique requirements.

  • 2. Site Evaluation

    Our team conducts a comprehensive evaluation of your property, considering factors like lot size, utility connections, zoning restrictions, and potential site challenges. This step ensures your ADU is strategically designed to maximize functionality and blend seamlessly with your existing property.

  • 3. Design & Planning

    Collaborating closely with you, we develop a detailed plan that aligns with your vision while adhering to Massachusetts' strict zoning and building regulations. From layout options to material selection, we ensure every aspect of the design is tailored to your needs and aesthetics.

  • 4. Permitting

    Permits can be complex, but our extensive experience with local municipalities allows us to handle the permitting process smoothly. We manage all the paperwork, inspections, and requirements so you can focus on what matters—seeing your project come to life.

  • 5. Construction

    With precision and care, we bring your ADU to life using only the highest quality materials and industry-leading practices. From foundation work to finishing touches, our construction process is efficient, eco-conscious, and ensures long-lasting durability.

  • 6. Regular Updates & Communication

    Transparency is key. Throughout the project, we provide consistent updates on progress, timelines, and any unforeseen developments. You’ll always know what’s happening and have direct access to our team for questions or adjustments.

  • 7. Quality Check & Final Walkthrough

    Before handing over the keys, we conduct a rigorous quality check to ensure your ADU meets our exacting standards. During the final walkthrough, we’ll go over every detail with you to confirm that the finished product aligns perfectly with your expectations.

  • 8. Post-Construction Support

    Our relationship doesn’t end when the project is complete. Whether it’s a question about maintenance or a future upgrade, you can count on us for continued support long after your ADU is finished.

Built Specially For You

Popular Uses for ADUs in Masschusetts

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Rental Income

Maximize your property’s potential by creating a fully independent rental unit. With high demand for affordable housing in Massachusetts, an ADU can generate steady income while increasing the overall value of your home.

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In-Law Suite

Provide aging parents or extended family with a safe, comfortable, and private living space close to home. ADUs allow for multigenerational living without sacrificing personal privacy or independence.

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Home Office

Escape the distractions of home life with a quiet, purpose-built space for work, art, or other creative pursuits. Whether you’re running a business or exploring a passion, an ADU gives you the room to focus and thrive.

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Guest House

Host friends or family in style with a cozy, self-contained space that offers both comfort and convenience. An ADU allows visitors to enjoy privacy while remaining close to the main home.

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Recreational Space

Turn your ADU into a personal retreat for hobbies or leisure. Whether it’s a yoga studio, a music room, or a game lounge, an ADU can be customized to enhance your lifestyle.

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Student Housing

Create an affordable, separate living area for college students or young professionals. ADUs are a great option for providing independence while maintaining proximity to home or campus.

OUR WORK

Our Recent Projects

Concord, MA

New Home Build

Canton, MA

Kitchen Remodel

Hingham, MA

Attic Remodel

Walpole, MA

Hardscaping, Exterior Remodel

Medfield, MA

Bathroom Remodel

Needham Heights

Full Home Remodel

Lexington, MA

New Home Build

Hopkinton, MA

New Home Build

Wayland, MA

New Home Build

Sudbury, MA

New Home Build

Newton, MA

New Home Build

Carlisle, MA

New Home Build

East Greenwich, RI

New Home Build

Walpole, MA

Kitchen Remodel

Sharon, MA

New Home Build

Medfield, MA

Kitchen Remodel

Sharon, MA

Kitchen Remodel

Mansfield, MA

Kitchen Remodel

Century Oaks

Hardscaping and Landscape

Medfield, MA

New Home Build

Newton, MA

New Home Build

Middletown, RI

Exterior Remodel

Wellesley, MA

New Home Build

Boxford, MA

New Home Build

Osterville, MA

New Home Build

Natick, MA

Kitchen Remodel
View more

TESTIMONIALS

Our Happy Clients

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★★★★★

Victor and his crew were awesome. Their ability to get things done and overcome complex situations was amazing. More so, Victor was very honest, very friendly, and very straightforward. When we first started our project, it was supposed to be easy, but little did we know that it would turn out to be a nightmare. In spite of this, Victor was extremely knowledgeable, professional, patient, and courteous. If it had not been for him, I would have given up. Throughout the entirety of the project, he was very meticulous about everything, which is something his team is very aware of. He encountered a tremendous amount of headaches; however, he never gave up, not once. Instead, every obstacle he faced that could not be figured out in the moment turned into a "let me think about this and I will get back to you," and within hours or days, he would come back and say, "how about we do it this way instead?"

Personally, I loved working with Baystate Group Builders and I will definitely do business with them again.


- Rosemary Ferreira

★★★★★

We needed a complete renewal (basement was remodeled over 20 years ago). We interviewed four contractors before selecting Vic. Vic's professionalism and personality were deciding factors in his selection. We carefully reviewed his previous work and his proposal to completely remodel our basement. Vic's pricing seemed very reasonable and after the perusal of the other contractors submitted proposasl, we decided Vic was the right person for our job. Our basement was completed recently and overall we are very happy with Vic's craftsmanship. We had absolutely no issues with Vic or members of his company. Everyone was very professional and clean. We would certainly use Vic again for other construction projects. Job well done Vic !!!


- Kevin Boyle

★★★★★

Victor and his team are amazing to work with. Extremely professional and absolutely meticulous when it comes to every aspect of the project. From the carpeting to carpentry to painting to electrical work to literally everything, we were blown away. The custom built entertainment unit is absolutely amazing as we gave our vision to Victor and he recreated it perfectly.


- Joseph Wyrwa

★★★★★

Baystate Group Builders are one of the best contractors I have worked with. Victor is always professional and honest in regards to the project. Victor and his team have upgraded our deck, renovated our master bath and finished our basement. Each project was completed on time and without surprises. Victor is one of the few contractors I trust in my home; simply one of the best out there.


- Tammie Lombardo

ADU FAQs

  • What is an Accessory Dwelling Unit (ADU)?

    An ADU is a self-contained residential unit located on the same lot as a primary dwelling. It includes its own entrance, kitchen, bathroom, and living area, providing independent living space. ADUs can be attached to the main home, such as a basement or garage conversion, or detached as a separate structure.

  • Are ADUs legal in Massachusetts?

    Yes, ADUs are legal in Massachusetts. In August 2024, Governor Maura Healey signed the Affordable Homes Act, which, among other provisions, allows for the construction of one ADU up to 900 square feet by right on a property in single-family zoning districts across all Massachusetts communities. 

  • What are the size limitations for ADUs?

    Under the Affordable Homes Act, an ADU can be no larger than 900 square feet or half the size of the principal dwelling's gross floor area, whichever is smaller.

  • Do I need a special permit to build an ADU?

    No, the new legislation prohibits municipalities from requiring a special permit or other discretionary zoning approval for the use or rental of an ADU in single-family residential zoning districts. 

  • Are there parking requirements for ADUs?

    Municipalities cannot require more than one parking space for an ADU located outside 0.5 miles from a commuter rail station, subway station, ferry terminal, or bus station. For ADUs within 0.5 miles of such transit stations, municipalities cannot require any parking spaces.

  • Can I rent out my ADU?

    Yes, you can rent out your ADU. The Affordable Homes Act prohibits municipalities from unreasonably restricting the creation or rental of an ADU that is not being used as a short-term rental.

  • Are there owner-occupancy requirements for properties with ADUs?

    The new legislation removes explicit statutory authority for municipalities to impose owner-occupancy requirements for either the ADU or the principal dwelling.

  • When did these changes take effect?

    The changes to Section 3 of Chapter 40A of the General Laws, related to ADUs, became effective on February 2, 2025, which is 180 days from the effective date of the Affordable Homes Act.

  • How do I start the process of building an ADU?

    Begin by consulting with a professional builder experienced in ADU construction to assess your property's suitability and navigate the design, permitting, and construction processes in compliance with local regulations.

  • Where can I find more information about ADUs in Massachusetts?

    For detailed information, refer to the Massachusetts government's official resources on ADUs: 


    https://www.mass.gov/info-details/accessory-dwelling-units

Start Your ADU Project Today

Your perfect ADU is just a call away. Whether you’re looking to create additional living space or generate rental income, Baystate Group Builders has the expertise to bring your vision to life.

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