Adu estimate — Boston, MA | AccessoryDwellingUnit Solutions

Looking for adu estimate in Boston, MA? Call AccessoryDwellingUnit Solutions for a contact a provider — no obligation. Licensed adu builders serve Boston and the surrounding area, and you'll get straight answers on timing and what affects the price.

Last updated: September 24, 2026

What affects the price

Building an ADU involves several moving parts that shape your total budget. The biggest factor is whether you choose a prefabricated unit or a custom build on-site. Site preparation is also significant; if your land requires extensive grading, utility trenching, or foundation work, costs will climb. Your choice of finishes—like kitchen cabinetry, flooring, and siding materials—also shifts the bottom line. We help you navigate these variables to find a setup that fits your property. Exact pricing confirmed free on the call.

About this service

An ADU estimate provides a preliminary look at what your secondary unit might cost based on the size and complexity of your plans. Variables such as foundation type, square footage, and interior material quality shift the total investment up or down. You need an estimate early in the process to help determine if your vision aligns with your available budget. Exact pricing confirmed free on the call.

Frequently asked in Boston

How do I find an accessory dwelling unit near me in Boston?

What does an accessory dwelling unit mean?

An accessory dwelling unit (ADU) means a secondary, independent living space on a single-family lot. It can be attached or detached from the main house. ADUs provide extra housing for family, renters, or as a home office. They are a flexible way to increase property utility. We help you explore ADU possibilities.

What's the ADU permit process in Boston?

What type of ADU housing is suitable for Boston?

Suitable ADU housing in Boston often includes basement conversions, garage additions, or small, detached backyard units. These designs must comply with strict zoning and space limitations. Maximizing the use of existing structures is common. We help you find pros who understand Boston's unique building environment.

Can I find an accessory dwelling unit contractor in New Hampshire?

What are modular accessory dwelling units?

Modular accessory dwelling units are factory-built components assembled on-site. This construction method can speed up the building process. It also often leads to cost efficiencies. The quality of modular units is typically high. We can help you find pros experienced with modular ADU construction in Boston.

How much does an ADU unit cost in Boston?

Also serving nearby: Quincy · Cambridge · Lynn · Newton · Brockton

All cities in Massachusetts →

More on this: HUD ADU resources — ADU policy and financing research.

Service area details

653,833residents

13,525per sq mile

8ZIP codes served

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, South End, North End, Charlestown — and every surrounding area.