ADUs and In-Law Apartments
A private, independent home on your property for a parent, an adult child or a long-term tenant, designed, permitted and built by one licensed contractor.
Request an EstimateA 1,900 Sq Ft ADU in Reading, MA
An ADU addition built by Alvesco Construction beside the existing home, from excavation and framing to a finished kitchen and tiled bathroom. See the full photo journey.
Room for Family, or a Rental Unit
An accessory dwelling unit (ADU) is a complete, separate home on the same lot as your house, with its own entrance, kitchen, bathroom and sleeping area.
Family Living
A mother-in-law apartment or in-law suite keeps parents or grown children close while everyone keeps their own space and privacy.
Rental Income
A long-term rental unit can help offset your mortgage, taxes or the cost of the project. Many homeowners plan for family now and a rental later.
Four Ways to Add a Unit
Attached Additions
A new wing or second story connected to your home with its own entrance, tied into your existing foundation, roofline and utilities.
Garage Apartments
A living unit above a new or existing garage, with plenty of separation without using more of your yard.
Basement & Attic Conversions
Space you already have, turned into a separate unit with proper egress, insulation, ventilation and its own entrance.
Detached Backyard Cottages
A small standalone home on its own foundation, the most private option for family or tenants.
Inside the Reading ADU
A closer look at the finished space and details.
What the State Law Allows
Since February 2, 2025, Massachusetts allows one ADU by right on most single-family lots.
Your town can’t require a special permit for that first ADU. A by-right ADU can be up to 900 square feet or half the size of your home, whichever is smaller. The owner doesn’t have to live on the property, so the unit can be rented long-term, although towns can still limit short-term rentals. The ADU must meet the building code and your town’s reasonable dimensional rules. Boston has its own ADU rules.
Larger units may still be possible depending on your town’s zoning. We confirm your setbacks, lot requirements and permit path before design starts.
Clear Steps From the First Visit to Move-In
1. Consultation
We review the lot, the existing house, utilities and access, and who the unit is for.
2. Design & Budget
We define layout, finishes and scope, coordinating architects and engineers when needed.
3. Permits
We prepare applications and coordinate inspections with your town.
4. Construction
Foundation, framing, utilities, insulation, finishes and the separate entrance.
5. Completion
Final inspection, walkthrough and project closeout.
What Affects the Cost
Every ADU is priced after a site visit. The biggest factors are the type of ADU (a conversion usually costs less than new construction), foundation and site work, utility connections for water, sewer, electrical and heating, the kitchen and bathroom, and your finish selections.
Discuss Your ProjectADU Questions
Can I rent out an ADU in Massachusetts?
Yes. The state law no longer lets towns require the owner to live on the property. Your town may still regulate short-term rentals.
Do I need a special permit?
Not for the first ADU on most single-family lots. You still need a building permit, and the unit must meet your town’s reasonable dimensional rules.
How big can an ADU be?
Under the by-right rule, up to 900 square feet or half the floor area of your home, whichever is smaller. Larger units depend on your town’s zoning.
Is an attached or detached ADU better?
It depends on your lot, budget and who will live there. Attached units usually cost less to connect to utilities; detached cottages offer the most privacy. We walk through both on the site visit.
Do you handle design and permits?
Yes. We coordinate design, engineering when needed, permits and inspections as part of the project.
More Ways to Add Space
See our home additions, attic and basement remodeling, and our article on planning an in-law suite addition.
Ready to Plan Your ADU?
Tell us your town, who the unit is for, and any photos or plans you have.
Request an EstimateCall (978) 595-4949
