ADU Builder South Shore, MA
Accessory Dwelling Units • In-Law Suites • Garage Conversions • Basement ADUs
SJ Wilson Construction specializes in designing and building high-quality Accessory Dwelling Units (ADUs) throughout the South Shore of Massachusetts, including Whitman, Hanson, Halifax, Rockland, Abington, Hanover, Weymouth, Marshfield, and surrounding towns. Whether you're creating an in-law suite for family, converting a garage into a private apartment, finishing a basement into a legal rental unit, or planning a detached backyard cottage, our team delivers full frame-to-finish expertise on every ADU build. We handle permitting, structural work, utilities, interior finishes, and everything needed to bring your new living space to life.
Why Build an ADU?
Multigenerational living (in-law suite or guest space)
Rental income / long-term investment
Extra private living space
Aging-in-place solutions
Home office, studio, or flexible use space
Major property value increase
✔ Attached ADUs
Direct additions connected to the home.
✔ Detached ADUs
Backyard cottages or standalone units.
✔ Garage Conversions
Turn an unused garage into a fully finished living area.
✔ Basement ADUs
Convert your basement into a legal living space with kitchen + bath.
✔ Over-Garage Additions
Complete living unit built above an existing garage.
What We Build
Why Choose SJ Wilson Construction
Choosing the right contractor is the most important part of any ADU project. At SJ Wilson Construction, we bring the experience, reliability, and craftsmanship needed to deliver a safe, beautiful, and fully compliant living space.
✔ Family-Owned South Shore Contractor
Local, reliable, and committed to high-quality work with personal service from start to finish.
✔ Full Frame-to-Finish Expertise
We handle everything—structural framing, utilities, kitchens, bathrooms, finishes, and inspections.
✔ Clear Communication & Professionalism
Homeowners work directly with our team, ensuring transparency, updates, and no surprises.
✔ Skilled Work Across All Trades
Electrical, plumbing, HVAC, flooring, trim, and siding—your ADU is built by experienced pros.
✔ Code-Compliant ADU Construction
We make sure your ADU meets all Massachusetts building codes, zoning rules, and safety standards.
✔ Reliable Scheduling & Clean Workmanshipr
We respect your home, timeline, and property throughout the entire project.
📞 Start Your ADU Project
Ready to explore options for an in-law suite, garage conversion, basement ADU, or detached unit?
Reach out and we’ll schedule a free on-site consultation to review your property and discuss your project.