
ADU Builder in Central Maine
Standalone or garage-integrated accessory dwelling units, built with full residential systems.
- 6Years building across Central Maine
- 30+Homes built, start to finish
- 1Owner who walks every job
An ADU is an accessory dwelling unit: a second small home on your property, either standalone or built into a garage. Garage Builders Maine builds them across Kennebec and Lincoln County, in towns like Augusta, Waterville, Gardiner, Winthrop, and Wiscasset.
These are full homes with real plumbing, electrical, and HVAC, not a stripped-down mini-build. Every ADU starts with zoning, and the owner handles those conversations with your town before we design anything.
The owner also walks your lot in person first, then gives you a straight answer on what fits and what it costs. Standalone or garage-integrated, priced for your property.
Why homeowners pick us
We build the ADU your property and your local zoning actually allow, not a generic model pulled off a catalog.
- Zoning checked with your town before we design anything
- Full residential systems, not a stripped-down mini-build
- Standalone or garage-integrated, priced for your lot

Reviews
What homeowners say
Very quick, efficient, and enjoyable to work with. Everyone was so friendly, and I was so pleased with the way it came out.
Did an amazing job on our new bathroom remodel.
Overall, the experience was overwhelmingly positive, marked by consistently excellent communication.
Other work we do
Find the shop
Our shop in Augusta, ME
219 Capitol St. Ste. 8Augusta, ME 04330
Zoning and site evaluation, before design
ADU rules vary town by town in Maine, and they change more often than most other permitting categories. We check current local zoning with your town before we design anything, rather than assuming a blanket rule applies.
Standalone versus garage-integrated
A standalone ADU gives you full site placement flexibility. A garage-integrated unit shares structure with an existing garage, which can lower cost but depends on what that garage can support.
Full systems, not a shortcut build
Plumbing, electrical, and HVAC all get sized for year-round occupancy, not a seasonal guest space. Septic capacity is a common gating factor on rural lots, and we check it early.
How it works
Get your free estimate.
We check zoning and site conditions with you before design.
We build it.
Standalone or garage-integrated, full systems, one crew.
Final walkthrough.
You inspect the finished unit before it's occupied.

Worth knowing
What an ADU build actually involves
An accessory dwelling unit is a small, self-contained living space, separate from your main home, built either standalone or attached to a garage.
Standalone ADUs sit on their own foundation, giving you the most flexibility on placement but requiring a full utility run if one isn't already nearby.
Garage-integrated ADUs build living space above or alongside an existing garage, which can share some structure and utility runs, lowering cost, but depends heavily on what your current garage can support.
Full kitchen versus kitchenette changes both cost and how the space can legally be used, since some towns treat a full kitchen differently in their ADU ordinance.
Site utility work, new well or septic capacity versus tying into existing systems, is one of the biggest hidden cost variables on rural Kennebec and Lincoln County lots.
When to start: ADUs carry a longer lead time than most projects because of permitting and full residential-systems scope. Plan on 2 to 4 months minimum before groundbreaking, and confirm zoning with your town before you get attached to a design.

Homeowners housing aging parents or adult children, wanting rental income, or adding a home office or guest space that's genuinely separate from the main house.
ADU zoning in Maine is not uniform. What's allowed in Augusta may not be allowed the same way in a neighboring town, and the rules shift more often than standard building code. Confirming zoning before you commit to a design saves you from a costly redesign later. We never promise a plan will be approved by code enforcement, since that call belongs to your municipality, not us.
Ask specifically about septic and well capacity experience, since that's the factor that most often changes an ADU's final cost on a rural lot. A builder who raises utility capacity before you ask is one who's actually done this before.
How much an ADU costs in Maine
Treat the numbers below as ranges, not a firm quote.
| ADU type | Typical size | Estimated range* |
|---|---|---|
| Garage-integrated, kitchenette | 400 to 600 sq ft | $65,000 to $110,000 |
| Standalone, full kitchen | 500 to 800 sq ft | $110,000 to $190,000 |
| Standalone, larger unit | 800 to 1,000 sq ft | $180,000 to $260,000 |
Standalone versus attached, full kitchen versus kitchenette, and site utility work (new well or septic versus existing tie-in) move these ranges significantly.
Common questions
Why homeowners trust us
Good to know
Frequently asked questions
Rules vary town by town and change more often than most permitting categories. We confirm current zoning with your specific municipality before design, rather than assuming a blanket rule applies.
Yes, if the existing structure can support it. We evaluate that during the site visit, since not every garage foundation is built for additional load.
Not necessarily. Some towns distinguish between full kitchens and kitchenettes in their ADU ordinance, which can affect how the unit is classified and used. We check your town's specific rule before finalizing the design.
Septic and well capacity. A lot needing new septic capacity or a deeper well costs meaningfully more than one that can tie into existing systems.
No plan is guaranteed approval before submission. That decision belongs to your municipal code enforcement officer. We design toward current zoning and permit requirements to give your application the strongest possible footing.
Plan on 2 to 4 months for permitting and design before groundbreaking, then 3 to 5 months of construction depending on size and whether it's standalone or garage-integrated.
Next step
Ready to talk about your ADU
Reach out and we'll check zoning and site conditions with you and give you a straight answer on what's realistic.






