Looking for an experienced ADU builder in Tewksbury, Massachusetts? Bradley’s Building Solutions is a licensed, full-service ADU contractor helping homeowners across Tewksbury and the Merrimack Valley design, permit, and construct accessory dwelling units that add value, income, and flexible living space to their properties.
Whether you’re exploring a detached ADU for aging parents, a garage conversion ADU for adult children, or an attached ADU to generate rental income, our team manages every step of the ADU construction process — from the initial site visit to final inspection.
What Is an ADU?
An accessory dwelling unit, or ADU, is a secondary dwelling unit built on the same lot as a single-family home. An ADU can take several forms: a detached ADU standing alone in the yard, an attached ADU sharing a wall with the main house, or a conversion that transforms existing space — like a garage or basement — into an independent living space.
ADUs are allowed by Massachusetts law up to 900 square feet, and the size of a protected ADU is limited to half the size of the primary dwelling, whichever is smaller. This statewide ADU law has made building an ADU more accessible than ever for homeowners in Tewksbury, opening the door to detached ADUs, attached ADUs, garage conversions, and above-garage units without the zoning hurdles that once stood in the way.
Many homeowners choose to build an ADU for practical reasons: creating a guest suite for visiting family, providing privacy for aging parents or adult children through multi-generational living, generating rental income from a long-term tenant or short-term rentals, or simply adding functional living space like a home office or creative studio. ADUs also help address local housing shortages by adding rental units to the existing housing stock without new subdivisions or large-scale development.
Massachusetts ADU Law & Zoning in Tewksbury
Under the 2025 Massachusetts ADU law, accessory dwelling units up to 900 square feet are generally allowed by right on lots zoned for single-family homes, which has simplified zoning approval for many ADU projects. That said, lot size requirements, setbacks, and parking rules still vary by zoning district in Tewksbury, and some properties may require additional zoning approval depending on their specific lot configuration.
ADUs must comply with local building codes and zoning regulations, and building permits are required from Tewksbury’s Building Department before any structural work, site preparation, or utility connections begin. Permit applications for ADUs in Tewksbury are submitted electronically, and our team handles this permit process on your behalf — preparing detailed plans, architectural plans, and all required documentation to keep your ADU project code compliant from day one.
Because zoning laws and local regulations can change, we recommend a feasibility study early in the process. A feasibility study, combined with an initial site visit, tells us exactly what’s possible on your property before you invest in full architectural plans — protecting your budget and timeline.
Types of ADUs We Build
As experienced ADU builders, we build every major type of accessory dwelling unit:
Detached ADUs
Detached ADUs are standalone units offering maximum privacy — ideal for guest houses, in-law suites, or independent living spaces for aging parents or adult children. Detached ADUs generally take 6–10 months from permits to completion and generally cost more than internal conversions, but they offer the most flexible living space and the greatest separation from the main house.
Attached ADUs
Attached ADUs share walls with the main house for cost efficiency, making them a popular option for homeowners who want additional living space without the site preparation and utility coordination that a detached ADU requires.
Attached ADUs
Attached ADUs share walls with the main house for cost efficiency, making them a popular option for homeowners who want additional living space without the site preparation and utility coordination that a detached ADU requires.
Garage Conversion ADUs
Garage conversion ADUs transform an existing garage into livable, functional living spaces — a cost-effective way to create additional living space without expanding your building’s footprint. Garage conversions are one of the most popular ADU options among Tewksbury homeowners because they reuse existing structures and existing space rather than requiring new construction.
Above-Garage ADUs
Above-garage ADUs utilize vertical space above an existing garage for additional living areas, a smart way to maximize space on a smaller lot while preserving yard space below.
Above-Garage ADUs
Above-garage ADUs utilize vertical space above an existing garage for additional living areas, a smart way to maximize space on a smaller lot while preserving yard space below.
Why Build an ADU in Tewksbury?
Increased Property Value. ADUs can increase property value by 20–35%, making an ADU one of the more effective home improvements for building long-term equity in your primary residence.
Rental Income Potential. Renting an ADU can generate $1,500–$2,500+ monthly income, whether you rent it as a long-term rental unit or offer it as one of the growing number of short-term rentals in the Merrimack Valley. For many homeowners, this rental income is the primary driver behind building an ADU in the first place.
Multi-Generational Living. An ADU offers privacy for multi-generational living — a guest suite or in-law suite gives aging parents or adult children their own comfortable space while staying close to the main residence.
Flexible, Functional Space. Beyond rental units and in-law suites, ADUs provide flexible living space for family or guests — think home offices, creative studios, or a guest suite that adapts to your needs over time.
Addressing Housing Shortages. On a broader level, ADUs can help address local housing shortages by adding rental units to established neighborhoods without new large-scale development — a benefit for the Tewksbury community as a whole.
ADU Construction Costs
ADU construction costs vary widely depending on the size, type, and site conditions of your project. Detached ADUs generally cost more than internal conversions like garage conversions, since detached construction requires new foundations, site preparation, and full utility connections, while conversions reuse existing structures and existing space.
ADU construction costs are also affected by square footage, finishes, and the complexity of utility coordination — for example, properties that need new utility connections or significant structural work will see higher costs than a straightforward garage conversion. We provide a detailed, itemized estimate after your initial site visit so there are no surprises once construction begins.
Many homeowners finance their ADU with a HELOC (home equity line of credit) or a construction loan. It’s also worth noting that property taxes typically increase once an ADU is added, since the ADU increases your property’s assessed value — a factor to weigh alongside your expected rental income when planning your accessory dwelling unit project.
Why Choose Bradley's Building Solutions
Licensed & Insured — Builders must have licenses and insurance to operate in Massachusetts, and Bradley’s Building Solutions meets and exceeds these requirements on every ADU construction project.
Local Expertise — As Tewksbury-based ADU contractors, we know the zoning laws, local regulations, and permit process specific to the Building Department here — not generic statewide guidance.
Full-Service ADU Builders — From architectural plans through building permits, site preparation, and final inspection, we manage the entire ADU project so you don’t have to coordinate multiple contractors.
Quality Craftsmanship — Every detached ADU, attached ADU, and garage conversion we build reflects quality construction and quality craftsmanship, down to the concrete work and finish details.
Clear Communication — You’ll have a single point of contact and clear communication from your initial site visit through final inspection.
When vetting any ADU contractors, it’s advisable to check for proper licensing and homeowner reviews — we’re happy to provide references from recent projects in Tewksbury and the surrounding Merrimack Valley.
Serving Tewksbury and the Merrimack Valley
Bradley’s Building Solutions builds custom accessory dwelling units for homeowners throughout Tewksbury and the greater Merrimack Valley, including Andover, North Andover, Wilmington, Billerica, Chelmsford, and Lowell.
Serving Tewksbury and the Merrimack Valley
Bradley’s Building Solutions builds custom accessory dwelling units for homeowners throughout Tewksbury and the greater Merrimack Valley, including Andover, North Andover, Wilmington, Billerica, Chelmsford, and Lowell.
Start Your ADU Project Today
Whether you’re planning a detached ADU, an attached ADU, or a garage conversion, Bradley’s Building Solutions is the experienced ADU builder Tewksbury homeowners trust for quality construction from start to finish.
Contact us today by calling (978) 221-4253 or send us a message to schedule your initial site visit and get a clear, detailed plan for your ADU.
Request a Free Consultation & Quote
Start Your ADU Project Today
Whether you’re planning a detached ADU, an attached ADU, or a garage conversion, Bradley’s Building Solutions is the experienced ADU builder Tewksbury homeowners trust for quality construction from start to finish.
Contact us today by calling (978) 221-4253 or send us a message to schedule your initial site visit and get a clear, detailed plan for your ADU.
Request a Free Consultation & Quote
FAQs About ADUs
Do I need a building permit to construct an ADU in Tewksbury?
Yes. All accessory dwelling unit construction requires building permits from Tewksbury’s Building Department, and permit applications are submitted electronically. Depending on your property, zoning approval may also be required.
How big can an ADU be in Massachusetts?
Under state law, ADUs are allowed up to 900 square feet, and the size of a protected ADU is capped at half the square footage of the primary residence.
Can I rent out my ADU?
In most cases, yes. Many homeowners rent their ADU as a long-term rental unit or short-term rental to generate rental income, though local regulations should always be confirmed for your specific property.
How long does building an ADU take?
Detached ADUs generally take 3–6 months from permit approval to completion. Garage conversions and attached ADUs that reuse existing structures often move faster, since less new construction and site preparation is involved.
Will an ADU increase my property taxes?
Typically, yes — because an ADU increases your property’s assessed value, you can expect a corresponding increase in property taxes. This is generally offset over time by rental income and long-term property value gains.
Do I need new utility connections for my ADU?
It depends on the accessory dwelling unit type. Detached ADUs usually require new utility connections and additional permits, while garage conversions and attached ADUs can often tie into existing utility connections with less utility coordination.