Last updated: September 24, 2026
What affects the price
Building an ADU involves several moving parts that shape your total investment. The final figure depends heavily on whether you choose a prefab unit or a custom build from the ground up. Site conditions are another major factor; if your property requires extensive grading, utility trenching, or foundation work, costs will climb. You also have to consider your choice of finishes, like high-end appliances or custom cabinetry. Navigating local permit fees and impact assessments also adds to the total.
About this service
A professional company handles the heavy lifting, including architecture, engineering, permit submittals, and the actual construction labor. You need an experienced team when you want to ensure your unit is built to code, structurally sound, and completed on a predictable schedule. We act as your single point of contact, coordinating every trade and inspection so you aren't managing subcontractors yourself. We provide professional oversight from start to finish. Exact pricing confirmed free on the call.
Frequently asked in Boston
What are the disadvantages of ADUs in Boston?
Some potential disadvantages in Boston include navigating complex city zoning regulations, which can vary by neighborhood. You'll also need to consider potential impacts on your existing property's yard space or privacy. The upfront construction costs can be a significant investment. However, many of these are manageable with proper planning and professional guidance.
How much does an ADU cost in Massachusetts?
The cost of an ADU in Massachusetts, including areas around Boston, depends heavily on factors like size, design complexity, and site preparation needs. Factors like foundation type, chosen finishes, and accessibility for construction crews all play a role. It's best to get a personalized quote to understand the specific costs for your project in the Boston area.
What are the rules for ADUs in California?
California has specific statewide ADU laws designed to encourage their development, but local ordinances still apply. These rules often cover setbacks, lot coverage, and parking requirements. It's crucial to check the specific regulations in your city or county. This ensures your project complies with all legal mandates.
Is an ADU allowed in Maryland?
Yes, ADUs are permitted in many areas of Maryland, including Baltimore. However, local zoning laws dictate the specifics, such as minimum lot sizes, setback requirements, and owner-occupancy rules. It’s essential to consult your local planning department or a specialist for precise information.
What are the rules for ADUs in California?
California has statewide laws promoting ADUs, often setting minimum standards for size and allowing them in more residential zones. Local jurisdictions can implement additional requirements, but they generally can't prohibit ADUs entirely. Understanding these local nuances is key for a smooth build.
California has offered various grant programs to help homeowners build ADUs, including programs that have provided significant financial assistance. These grants aim to make ADUs more accessible. Eligibility criteria and funding availability can change, so it's wise to research current programs.
Also serving nearby: Quincy · Cambridge · Lynn · Newton · Brockton
More on this: HUD ADU resources — ADU policy and financing research.
Service area details
Serving all of Boston — population 653,833; about 13,525 residents per square mile across 48.3 sq mi. ZIP codes covered include 02108, 02109, 02110, 02111, 02112, 02113, 02114, 02115.
Neighborhoods served in Boston: Back Bay, Beacon Hill, Charlestown, Dorchester, Fenway-Kenmore, Jamaica Plain — and every surrounding area.
Areas we serve
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