Custom
ADU Builders
Serving the NH Seacoast, Lakes Region & Southern Maine
Accessory Dwelling Units (ADUS)
T and J Builders specializes in designing and building high-quality Accessory Dwelling Units (ADUs) for homeowners throughout Dover NH, Portsmouth NH, the New Hampshire Seacoast, the Lakes Region, and Southern Maine. Whether you’re looking to add rental income, create space for family, or increase your property’s value, our team delivers ADUs that are functional, beautiful, and built to last.
What Is an ADU?
An Accessory Dwelling Unit (ADU) is a secondary residential space located on the same property as a primary home. ADUs can be:
Detached backyard cottages
Attached additions
Garage conversions
Basement or in-law apartments
ADUs offer flexible living solutions while maintaining privacy and independence.
Why Build an ADU?
Homeowners across New Hampshire and Maine are choosing ADUs for many reasons, including:
Rental income to offset mortgage costs
In-law or multigenerational living
Guest housing or home offices
Aging-in-place solutions
Increased property value
T and J Builders helps you determine the best ADU option based on your property, budget, and long-term goals.
ADU Design & Construction Services
As experienced custom builders, we manage your ADU project from start to finish, including:
Site evaluation and feasibility
Custom ADU design
Permitting and zoning guidance
Foundation, framing, and structural work
Plumbing, electrical, and HVAC
Interior finishes and exterior details
We understand local zoning and building requirements in Dover, Portsmouth, and surrounding NH and Maine communities, helping ensure a smooth approval and construction process.
Why Choose T and J Builders?
✔ Local builders based in Dover NH & Portsmouth NH
✔ Deep knowledge of NH Seacoast & Southern Maine regulations
✔ High-quality craftsmanship and materials
✔ Clear communication and reliable timelines
✔ Custom solutions — no cookie-cutter designs
We take pride in building ADUs that seamlessly match your existing home while maximizing comfort, efficiency, and value.
Serving New Hampshire & Southern Maine
T and J Builders proudly serves homeowners throughout:
Dover NH
Portsmouth NH
New Hampshire Seacoast
Lakes Region NH
Southern Maine
If you’re unsure whether your property qualifies for an ADU, our team is happy to help.New Construction You Can Trust
Start Your ADU Project Today
Ready to explore adding an ADU to your property? T and J Builders is here to guide you every step of the way — from concept to completion.
📞 Contact us today to schedule a consultation and learn how an ADU can work for your home.