In-Law Suite
Private living space inside or attached to your home — typically a bedroom, sitting area, and bathroom, sometimes with a kitchenette. It can share an entrance and a kitchen with the main house.
Multigenerational living is back, and Massachusetts just made it much easier to build for. CJM Builders is an in-law suite and ADU builder serving North Reading, MA and the surrounding towns. We design and build suites that work for the whole household: a parent moving closer, a returning graduate who needs real privacy, or your own one-level living down the road.
In-Law Suite or ADU: What's the Difference?
Both add private living space — the difference is how independent that space is.
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Accessory Dwelling Unit (ADU)
A fully independent home on your property: its own entrance, full kitchen, bathroom, and sleeping area. That independence is what makes it a legal dwelling unit — and what opens the door to long-term rental income.
Which one you build depends on how connected you want the space to be, what your lot allows, and whether rental flexibility matters down the road. We’ll walk you through both during design.
Massachusetts Made ADUs Legal by Right
Under the Affordable Homes Act, passed in August 2024 and in effect since February 2, 2025, Massachusetts allows one ADU by right on most single-family lots statewide. In plain terms:
This is the biggest change to Massachusetts accessory-unit law in decades. If an in-law apartment was ever on your wish list, the path is now far clearer, and we handle the permitting through North Reading’s PermitEyes portal as part of every project.
Septic First: The North Reading Reality
Most North Reading homes run on private septic systems, and Title 5 ties a system’s capacity to the number of bedrooms it serves. Adding a suite or ADU usually means adding a bedroom — so we evaluate your septic capacity at the very start of planning.
Sometimes the existing system has room. Sometimes an upgrade belongs in the budget. Either way, you’ll know before design begins, not after. This is exactly the kind of local groundwork our Survey step exists for.
Ways to Add a Suite to Your Home
There’s more than one way to get there, and your lot usually points to the answer:
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Attached addition
A new wing with its own entrance — the classic in-law setup, built as a room addition scaled up to a suite.
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Above or beside the garage
A garage addition designed from day one to carry living space is one of the most efficient routes to a private ADU.
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Basement-level suite
Where ceiling height, egress, and moisture control allow, a walk-out basement can become bright, code-compliant living space.
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Detached cottage ADU
A small standalone unit, where lot size and septic capacity support it.
Designed for Comfort, Privacy, and the Long Run
A good suite respects everyone’s independence. We design for it deliberately: separate entrances, sound insulation in shared walls, and parking that doesn’t shuffle.
We also build for the years ahead — zero-threshold showers, wider doorways, lever hardware, and true one-level living. Done well, these choices are invisible until the day they matter. You’ll pick every finish in person at our Design Center & Showroom on Main Street in North Reading, and 21-month, 0% interest financing (opens in a new tab) is available to make the numbers work.
Built in from the start
- Separate entrances and parking that doesn’t shuffle
- Sound insulation in shared walls
- Zero-threshold showers and wider doorways
- Lever hardware and true one-level living
What an In-Law Suite or ADU Costs
In-law suites and ADUs price like other Massachusetts additions, with most falling in the $150 to $400 per square foot range, but land at the higher end when a full kitchen and bathroom are involved. A garage conversion typically costs less than a new detached cottage because the shell already exists.
Every project gets a written, itemized estimate before work begins, the same standard we bring to all our home additions in North Reading. Ready to see what your property allows? Request a free estimate or call (978) 649-7300. We build in North Reading, Andover, Middleton, Reading, Wakefield, Wilmington, and surrounding towns.
Frequently Asked Questions
Are ADUs legal in North Reading?
Yes. Since February 2025, Massachusetts state law allows one ADU by right on most single-family lots, including in North Reading. Local requirements for setbacks, building code, and septic capacity still apply, and we manage those approvals for you.
How big can an ADU be in Massachusetts?
State law caps an ADU at 900 square feet or half the gross floor area of the main home, whichever is less. Within that cap, a well-planned layout comfortably fits a bedroom, full bath, kitchen, and living area.
Can I rent out an ADU?
Yes — long-term rental is allowed, and the state law bars towns from requiring you to live in either unit. Short-term rentals are different: towns may restrict them, so check North Reading's current rules before planning Airbnb income.
Does an in-law suite need its own kitchen?
No. An in-law suite can share the main home's kitchen or use a kitchenette. A full, separate kitchen, along with its own entrance and bathroom, is what distinguishes a legal ADU from a suite.
Will an ADU work with my septic system?
It depends on your system's Title 5 bedroom capacity. Some systems have room for another bedroom; others need an upgrade first. We assess your septic capacity at the start of planning so the answer is built into your design and budget.
