Professional ADU Contractor in Massachusetts: MA ADU Renovation Services

If you're thinking about building an Accessory Dwelling Unit (ADU) in Massachusetts, you’re making a smart investment. As housing demands and property values continue to rise in Massachusetts, adding an ADU is a strategic way to maximize your space, boost property value, and even create an additional income stream. Whether you're envisioning a backyard cottage, a detached studio, or a basement ADU, understanding local ADU construction regulations is essential to a successful project.

At FiveTen Construction & Design, we are proud to be a trusted ADU contractor serving homeowners across Massachusetts. We specialize in comprehensive ADU construction and ADU renovation services, guiding you through every phase—from creative design concepts to expert building. Whether you need a brand-new MA ADU or want to transform an existing space into a functional accessory unit, our team ensures your project is completed legally, beautifully, and on time.

What Is an ADU?

An Accessory Dwelling Unit (ADU) is a smaller, independent residential living space built on the same lot as a single-family home. Think of it like a second, smaller home that shares the property with the main house.

Types of ADUs

  • Detached ADUs: A fully independent structure, ideal for rental income, guest homes, or private offices. Detached ADUs offer maximum privacy and design flexibility, making them a perfect choice for homeowners in Massachusetts looking to maximize their property’s potential. As experienced ADU contractors, we specialize in custom ADU construction to suit your needs.

  • Attached ADUs: Built onto your existing home, these units share a wall but have separate entrances and complete amenities. Attached ADUs are perfect for family members, tenants, or additional space. Whether you're looking for ADU renovation or a new build, our team ensures a seamless process in the MA ADU market.

  • Interior Upper Floor ADUs: Transform your attic or add an upper floor to create a new accessory dwelling unit (ADU). Ideal for homeowners who want to make the most of their vertical space, these Massachusetts ADUs are versatile and cost-effective.

  • Above Garage ADUs: Maximize your existing garage space by adding a unit above it. Above garage ADUs offer a practical way to expand your home’s livable area, providing options for rental income or additional space for family or guests.

  • Garage Conversions: Turn your unused garage into a functional ADU without expanding your home’s footprint. A garage conversion is a great way to create a cost-effective ADU with all the necessary amenities, perfect for families or tenants looking for affordable living in Massachusetts.

  • Basement ADUs: Many homes in Massachusetts, feature basements perfect for conversion into an ADU. As experienced basement ADU contractors, we specialize in transforming underutilized lower levels into stunning, income-generating apartments or functional spaces for family members.

Approved ADU Uses

  • Rent your ADU as a long-term rental to create consistent income.

  • Support multi-generational living (ideal for aging parents, adult children, or live-in caregivers).

  • Use it as a home office, art studio, or private guest space.

Unauthorized ADU Uses

  • Short-term rentals (like Airbnb or VRBO).

  • Selling your ADU separately from the main home is not permitted.

ADU Rules to Know for Your Massachusetts ADU Project

Before starting your ADU construction or ADU renovation project, it's important to understand the basic requirements for building an ADU in Massachusetts:

  1. Owner-Occupied Requirement: In Medford, MA, the property owner is not required to live on the premises when adding a Massachusetts ADU. This provides more flexibility for homeowners looking to generate rental income.

  2. Size Limits: Your ADU must be smaller than the primary residence. In Massachusetts, the maximum size allowed is up to 900 square feet, though this can vary by zoning district. Working with an experienced ADU contractor ensures your design meets all local requirements.

  3. Parking: Generally, an additional off-street parking space is required. However, homes located within ½ mile of a transit station are exempt from this rule, making ADU construction even more accessible in well-connected areas.

  4. Entrance: A separate entrance is typically needed for your MA ADU. It may share a porch or landing with the main house but must be distinct to qualify.

  5. Utilities: Separate utility connections are not mandatory for your ADU renovation or new build, helping to reduce overall project costs.

  6. Limitations: Only one accessory dwelling unit (ADU) is allowed per residential lot in Massachusetts.

  7. Occupancy Term: Long-term requires a minimum rental or occupancy term of 30 days for any ADU.

Navigating Massachusetts ADU rules can feel overwhelming, but partnering with an expert ADU contractor like FiveTen Construction & Design ensures your project stays compliant, efficient, and stress-free.

ADU Building Code Overview for Massachusetts ADUs

Whether you're planning a basement ADU renovation or starting new ADU construction, FiveTen Construction & Design—your trusted Massachusetts ADU contractor—ensures every project complies with state and local building codes. We handle all the critical details for a smooth and successful MA ADU build, including:

  • 1-Hour Fire Separation: A required fire-rated barrier between the main home and the accessory dwelling unit (ADU) to ensure occupant safety.

  • Ventilation and Natural Light: Proper airflow and sufficient natural light are key requirements for any livable Massachusetts ADU.

  • Minimum Room Sizes: Every habitable room must have at least 70 square feet of space and a minimum ceiling height of 7 feet.

  • Two Means of Egress: Safe and accessible exit routes are essential for emergency access in every ADU construction project.

  • Smoke and Carbon Monoxide Detectors: Interconnected alarms are required to provide maximum safety for both the main residence and the ADU.

  • Stretch Energy Code Compliance: We ensure your MA ADU meets Massachusetts' Stretch Energy Code standards for superior energy efficiency and sustainability.

If you're considering a basement ADU conversion in Medford, MA, or anywhere in the Greater Boston area, trust FiveTen Construction & Design—the experienced ADU contractor who will guide you through every step, from thoughtful design to final inspection.

Why Choose FiveTen Construction & Design as Your Trusted ADU Contractor?

Building an Accessory Dwelling Unit (ADU) in Massachusetts is more than just another renovation—it’s an investment in long-term property value and lifestyle flexibility. From navigating complex permitting to meeting strict building codes, Massachusetts ADU construction can feel overwhelming without the right expert by your side. That’s why partnering with an experienced MA ADU contractor like FiveTen Construction & Design is essential for a smooth, successful project.

Whether you're planning a detached MA ADU, an attached addition, or a basement ADU conversion, we offer the specialized knowledge needed to guide you through every step of the ADU construction process. Basement ADUs in particular require careful planning to meet Massachusetts building standards—and as a trusted basement ADU contractor, we deliver exceptional results without costly delays.

What You Can Expect When You Partner with FiveTen Construction & Design:

  1. Personalized Consultation
    We start by understanding your goals, vision, and property needs. Whether you're building a detached ADU, a garage conversion, or a basement ADU in Massachusetts, we walk you through every available option while ensuring full compliance with local and Massachusetts ADU regulations.

  2. Custom ADU Design
    If you're planning a basement ADU, we’ll design smart, efficient layouts, provide detailed renderings, and optimize every square foot for maximum functionality. For detached or attached ADUs requiring architectural and engineering plans, we guide you through plan reviews and design details—ensuring your ADU renovation is beautiful, functional and tailored to your goals.

  3. Transparent Budgeting
    We believe in clear, upfront communication about costs. Our detailed estimates, material selections, and transparent change-order process ensure your ADU renovation or construction stays on budget and on schedule.

  4. Expert Permitting
    Navigating the intricate Massachusetts ADU permitting process is one of our specialties. As an experienced MA ADU contractor, we manage all of the permit applications, and code compliance requirements to keep your ADU project moving forward smoothly.

  5. High-Quality ADU Construction
    At FiveTen Construction & Design, craftsmanship is at the heart of everything we do. Whether you’re building a detached Massachusetts ADU or completing a basement ADU conversion, we use top-quality materials and skilled trades to deliver beautiful, durable results that stand the test of time.

  6. Final Walkthrough and Client Satisfaction
    Upon project completion, we perform a detailed walkthrough to ensure every aspect of your new ADU meets our high standards—and yours. Your complete satisfaction is our top priority.

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