Massachusetts Acessory Dwelling Unit Law Updates
Updated 1/29/25
In recent years, Accessory Dwelling Units (ADUs) have become an increasingly popular addition to homes throughout Massachusetts. This year, their popularity will surge thanks to landmark legislation, the Affordable Homes Act, that was signed into law last summer by Governor Maura Healey.
What the Accessory Dwelling Unit Law Law Means to You
Starting February 2, the ADU provision to the Affordable Homes Act goes into effect. It will allow homeowners in single-family zoning districts in towns and cities throughout the state to build ADUs by right.
The provision was included in the law as one tool to help the state address the growing need for more housing. As a result of these homeowner-friendly regulations, it is estimated that 8,000 to 10,000 ADUs will be constructed over the next five years, adding to the diversity of housing stock in the Commonwealth.
By reducing the barriers to constructing ADUs, it lowers the costs for homeowners to build them on their properties. This is where RemodelWerks’ expertise can help you determine if an ADU is right for your property, and if so, where to build it — and how to build it — to best meet your needs.
See your ADU in 2D, 3D, and live walkthrough, before a construction contract is signed.
Here’s an example of a completed RemodelWerks ADU project: A homeowner wanted to convert their partially finished basement into a rentable accessory dwelling unit (ADU) for passive income. Our team ensured full code compliance, including proper egress, emergency exits, and clear separation from the main house, while integrating a functional kitchen and bathroom. Let us design and build the perfect ADU for you while ensuring compliance with ADU requirements and any additional local building codes that may impact your project.
ADU Considerations
Commonly known as in-law apartments, homeowners build ADUs for a number of reasons. Sometimes, it’s to give a loved one — a parent, grandparent, child, or grandchild — an affordable place to live that is in close proximity to you. ADUs are a great way to care for parents or grandparents, allowing them to safely age in place while giving them space to maintain their independence.
Homeowners may also want to consider an ADU if they have frequent visitors, giving them added comfort and increased space during their stay.
Other times, it’s a way to generate revenue from your property by renting out the ADU, helping offset mortgage payments and increasing household income.
If you work from home, an ADU is a great option to build a private office or studio space that truly meets your professional needs.
ADUs also add to the value of your home and serve a functional purpose to accommodate your existing (and future) lifestyle needs and family dynamics.
ADUs cannot be more than half of the total square footage of the primary house, or a maximum of 900 square feet, whichever is smaller. As an example, a 1,400-square-foot house cannot have an ADU larger than 700 square feet.
Along with size limitations, ADUs must maintain a separate entrance that meets the building code’s safety standards.
In constructing an ADU, homeowners must adhere to all zoning setbacks, health and safety requirements, and parking requirements. Towns may impose additional restrictions that could include the prohibition of ADUs being used as short-term rentals (e.g., Airbnb or VRBO).
While the new laws make it easier for homeowners to navigate permitting, RemodelWerks can help you through this process, which can still be time-consuming and confusing.
Types of ADUs
ADUs can either be freestanding or connected to a home. Depending on your lot size, we can determine which option is best suited for your property.
External ADUs are standalone structures that may include a small cottage or home, or a separate in-law suite constructed over the garage. This offers more privacy to both homeowners and anyone staying in the ADU, making it ideal for renters or family members living on-site.
An internal ADU is connected to the existing home. Some examples of internal ADUs include a renovated basement, garage, attic, or an addition to the home.
Regardless of which option you choose (external or internal), your ADU must include a kitchen, bathroom, and bedroom, providing independent living for occupants.
Why Choose RemodelWerks for your ADUs
At RemodelWerks, our team will work with you to determine which option best suits your needs. We employ a thoughtful, strategic approach to every project and are committed to quality craftsmanship and exceptional customer service that will simplify the ADU building process, from start to finish.
With more than a decade of home building and remodeling expertise in Massachusetts, RemodelWerks delivers trusted solutions through every phase of construction. We look forward to serving and supporting you as you explore adding an ADU to your property.
Why Do People Create Accessory Dwelling Units?
ADUs are increasingly popular because they address both practical and emotional needs. They provide a flexible and affordable solution to modern housing challenges while fostering closer family connections and financial stability.
Family Living Arrangements
Many homeowners build ADUs to accommodate family members. For aging parents or grandparents, an ADU offers a perfect balance of proximity and independence. Seniors can maintain their autonomy in a safe, familiar environment while having loved ones nearby for support. This arrangement often avoids costly alternatives like assisted living facilities, which can strain finances and emotional well-being.
Young adults transitioning into independence also benefit from ADUs. In today’s challenging economic climate, where student debt and housing costs are high, an ADU gives them a place to live without the burden of high rents. Similarly, multigenerational families use ADUs to strengthen ties while respecting personal space.
Cost Savings Compared to New Homes
Building an ADU is far more cost-effective than buying or constructing a new home. The average cost of constructing an ADU is typically a fraction of what it would take to purchase a single-family home in the same area. For families looking to expand their living space without breaking the bank, an ADU is an ideal solution.
ADUs maximize the use of existing property. Instead of buying additional land or building an entirely separate structure, homeowners utilize their current lot for a smaller, energy-efficient unit. This reduces overall living expenses, from mortgage payments to utility bills, as ADUs are often designed with modern energy-saving technologies.
Additionally, ADUs can generate rental income, helping homeowners offset their mortgage payments. For example, a homeowner who rents out an ADU for even a modest monthly amount could significantly lower their housing expenses over time.
ADUs for Lifestyle Flexibility
An ADU adds flexibility to a property, accommodating changing family needs and dynamics. Whether it’s a space for visiting relatives, a home office, or a rental unit, an ADU adapts to the homeowner’s lifestyle. This adaptability is invaluable in today’s fast-paced world, where family needs can evolve rapidly.
For remote workers or entrepreneurs, ADUs offer a private, distraction-free workspace. The convenience of working steps away from home enhances productivity while avoiding the high costs of renting office space elsewhere.
Environmental and Community Benefits
ADUs are a sustainable solution to the housing crisis. By building smaller, more efficient homes on existing lots, homeowners reduce urban sprawl and the environmental impact of new construction. Additionally, ADUs help increase housing stock without altering the character of established neighborhoods.
For communities, ADUs address housing shortages by offering affordable rental options. These units are perfect for teachers, healthcare workers, or young professionals who need cost-effective housing close to their workplaces.
About RemodelWerks
RemodelWerks is dedicated to giving you a superior custom building and remodeling experience. We offer turn-key planning, 3-D design, architectural design, and construction services on Accessory Dwelling Units and every other area of your home.