Custom accessory dwelling units for Eastern Massachusetts, New Hampshire, and Maine. Professional project management during construction. Lifetime support after.
Bradford Construction Management designs and builds custom accessory dwelling units (ADUs) across Eastern Massachusetts, New Hampshire, and Maine. Most Bradford ADUs are built with insulated concrete forms (ICF), are customized for each property, and finish in about a month once permitting and site work are done. Pricing starts at $400 per square foot on a transparent cost-plus model, with a not-to-exceed budget set before construction and permits, professional finishes, and appliances included. Every project comes with daily job-site photo updates, one accountable project manager, and lifetime support through Bradford Home Services. Bradford is licensed and insured (MA HIC #201908) in Massachusetts and New Hampshire.
A private home for aging parents - close enough to help, private enough to thrive. An alternative to assisted living that keeps families together.
A fully-equipped guest suite that pays for itself through short or long-term rental. Separate entrance and utilities make hosting simple.
A dedicated workspace steps from your door - no commute, no distractions. Perfect for remote professionals, artists, or creative studios.
Add living space to your vacation home or lake house in New Hampshire. Double your hosting capacity without doubling your footprint.
Adult children, extended family, or boomerang kids - everyone gets their own space while staying connected. Together, but independent.
A comfortable retreat for visitors that beats the pull-out couch. Give guests their own private space while keeping your home to yourself.
If you are reading this, you are thinking about adding something meaningful to your property - whether that is a place for aging parents to stay close, a guest suite that earns its keep, a workspace that is truly separate from home, or simply more flexibility for whatever life brings next.
I started Bradford's ADU program because I saw too many families facing impossible choices - and too many homeowners getting burned by contractors who disappeared after the deposit cleared.
We do things differently. Every project gets daily documentation and professional project management. And through Bradford Home Services, we are still here for you years after the last nail is driven.
Rick White
Founder, Bradford Construction Management
Design views, concept layouts, transparent pricing, and financing options - design guidance to help you start planning. Enter your info below and we will send it right over.
Five design starting points, customized for each customer and property.
A one-level cottage with open kitchen and living space, a separate bedroom, and a combined bath and laundry.
Living Space
One-level living
Bedrooms
1 Bedroom
Bathrooms
1 Full Bath
Outdoor Space
Covered Patio
Typical Pricing
$400+/SF
The per-square-foot rate moves with finishes, construction method and site conditions. Garage and outdoor areas are excluded from stated living-area figures; full project scope determines the budget.
A cottage with living space beside an attached single-car garage. The open kitchen and living area lead to a separate bedroom with rear patio access.
Living Space
600 SF Living
Bedrooms
1 Bedroom
Bathrooms
1 Full Bath
Garage
1-Car Garage
Typical Pricing
$400+/SF
The per-square-foot rate moves with finishes, construction method and site conditions. Garage and outdoor areas are excluded from stated living-area figures; full project scope determines the budget.
A one-bedroom apartment above a two-car garage. The second-floor living space includes a kitchen, pantry, walk-in closet and laundry.
Living Space
850 SF Living
Bedrooms
1 Bedroom
Bathrooms
1 Full Bath
Garage
2-Car Garage
Typical Pricing
$400+/SF
The per-square-foot rate moves with finishes, construction method and site conditions. Garage and outdoor areas are excluded from stated living-area figures; full project scope determines the budget.
Our most versatile single-story design, available in four exterior styles.
Living Area
514 SF + 86 SF loft
Bedrooms
1 Bedroom
Bathrooms
1 Full Bath
Footprint
32' x 19'
Typical Pricing
$400+/SF
The per-square-foot rate moves with finishes, construction method (wood-framed or ICF), and site conditions.
Main level: 514 SF of living area
Loft: 86 SF of living area; 600 SF total with main level
Two-story design with rooftop deck, ideal for smaller lots.
Living Area
726 SF total
Bedrooms
1 BR + Flex Loft
Bathrooms
1 Full Bath
Special Feature
Rooftop Deck
Typical Pricing
$400+/SF
The per-square-foot rate moves with finishes, construction method (wood-framed or ICF), and site conditions.
Main level: 547 SF of living area
Upper level: 179 SF; 726 SF total living area. Roof deck: 162 SF, separate.
A custom configuration with 900 SF of living space, two bedrooms, one bath and a rear deck above a detached two-car garage. The 850 SF, one-bedroom Kingsbury remains a separate starting configuration.
900 SF custom example: two bedrooms, one bath, rear deck and exterior stair.
Real photos from an active Bradford ICF build. Insulated concrete form (ICF) walls go up fast and create an energy-efficient, solid shell.
Cost-plus delivery with a detailed estimated not-to-exceed budget before construction. Every change documented in writing before it happens. You see every cost.
See exactly what happened on your job site every single day. No more wondering, no more chasing down your builder for answers.
Our ICF construction system lets us build your ADU in about one month from groundbreaking.
Delivered complete with professional finishes, fixtures, and appliances. We coordinate permits and inspections so you do not have to chase paperwork.
From design through build, one team manages every detail. No handoffs, no miscommunication between separate contractors.
Through Bradford Home Services, you have a permanent support team for maintenance, repairs, and warranty work - for as long as you own your home.
ADUs are not for every situation. Here is how to know if one makes sense for your property and goals.
Separate, self-contained living space
Expanding your existing home
Learn about our addition services
Bradford builds on a transparent cost-plus delivery model. You receive a detailed estimated not-to-exceed budget before construction begins, covering every line item.
Typical Pricing
$400+/SF
Starting rate, adjusted for site conditions, construction method (wood-framed or ICF), finish package, and customization. A site walk gives us what we need to price your project.
The Hoyt, The Lincolnshire and The Kingsbury are evolving design starting points. Each is customized.
Site-specific costs (utility connections, permitting fees, septic) are listed separately in your budget after our site assessment, before any work begins. Financing options may be available depending on your situation.
Massachusetts changed the rules in a big way. Section 8 of the Affordable Homes Act took effect February 2, 2025, and the state's ADU regulations (760 CMR 71.00) spell out how towns must apply it. You can now build one accessory dwelling unit by right on a lot in any single-family zoning district in the state. By right means your town cannot require a special permit or a discretionary hearing just to allow the unit.
The state calls this a Protected Use ADU. It has to have its own entrance, and it can be no larger than 900 square feet or half the gross floor area of your main house, whichever is smaller. A 1,600 square foot home, for example, can have an ADU of up to 800 square feet. A second ADU on the same lot is still possible in some towns, but it goes back to needing a special permit.
Towns still set local rules, but the state limits how far those rules can go. Here is how the main requirements work under the state regulations.
| Requirement | What the state rules say |
|---|---|
| Special permit | Not allowed for one ADU in a single-family district. The unit is allowed by right. |
| Size | No more than 900 sq ft or half the main home's gross floor area, whichever is smaller. |
| Owner occupancy | A town cannot require you to live in the main house or the ADU. |
| Parking | No more than one added space. None can be required if any part of the lot is within half a mile of a transit station. |
| Minimum lot size | A town cannot set a minimum lot size for a Protected Use ADU. |
| Attached or detached | A town cannot require the ADU to be attached, or require it to be detached. |
| Setbacks, height and lot coverage | Can apply, but no stricter than the rules for the main house or an accessory building in that district, whichever is more flexible. |
| Site plan review | Allowed, but it must use clear and objective standards. |
| Septic | Title 5 still applies, with no stricter septic rules than a single-family home in that district would face. |
| Short-term rentals | Towns can restrict or ban short-term rentals of an ADU. Long-term rental is allowed. |
| Floodplain or aquifer overlay | A special permit can be required if the main house would need one, based on clear, objective criteria. |
Source: Massachusetts Executive Office of Housing and Livable Communities, 760 CMR 71.00. Your town's bylaw and your lot decide the details, so we confirm them for every property before design starts.
Every town runs its own paperwork, but most Massachusetts ADU projects move through the same steps.
State law lets you choose, so the right answer comes down to your lot, your budget and how the space will be used.
| Question | Attached ADU | Detached ADU |
|---|---|---|
| What it is | Part of the main house, such as an addition, an above-garage unit or a converted wing | A separate building in the yard, such as a backyard cottage or a unit over a detached garage |
| Size, setbacks and height | The same state limits apply to both types (see the rules table above) | |
| Utilities | Usually extends the home's existing water, sewer or septic, and electrical systems | Needs trenching to run water, sewer or septic, and electric out to the new building |
| Privacy | Shared wall, with its own entrance | The most separation for both households |
Under the state regulations, your town cannot require separate water, sewer or electric connections for the ADU. A separate connection can still be required by the utility company itself, by state law, or by a local, regional or state board. Here is what we look at on every lot.
Every town applies the state law through its own bylaw. See what building an ADU looks like in the communities where we work most:
Building in New Hampshire or Maine instead? Each state sets its own ADU rules. New Hampshire's ADU law is covered in the next section.
Since July 1, 2025, every New Hampshire town has to allow one accessory dwelling unit, attached or detached, as a matter of right on a lot where a single-family home is allowed. The change came from HB 577, which rewrote RSA 674:72. Towns can no longer require a conditional use permit or a special exception for that first ADU. Before the change, state law only guaranteed an attached unit, and a town could require a conditional use permit or special exception for a detached one.
Bradford Construction Management is based in Plaistow, NH and builds ADUs across Southern New Hampshire and the Seacoast as well as Massachusetts. Plaistow sits on the Massachusetts border, so we work under both states' rules every day. They handle size, owner occupancy and septic differently, and those differences change what we design.
Towns still write their own ADU ordinances, but the state sets the floor. Here is what RSA 674:72 allows a town to ask for, and what it rules out.
| Requirement | What the state law says |
|---|---|
| Permit | One ADU is allowed as a matter of right. No conditional use permit or special exception. A building permit is still required. |
| Attached or detached | Either one. The town cannot limit you to an attached unit. |
| Size | Up to 950 sq ft of living space unless the town allows more. A town cannot cap an ADU below 750 sq ft. |
| Owner occupancy | A town may require the owner to live on the property, but it cannot say which unit the owner lives in. |
| Parking | A town can require up to one added space for the ADU. |
| Lot size, frontage and setbacks | No extra lot size, frontage, setback or design review requirements beyond what a single-family home faces in that zone. |
| Water and septic | The property has to show adequate water and sewage disposal under RSA 485-A:38. Separate systems for the ADU cannot be required. |
Source: New Hampshire RSA 674:72, as amended by HB 577 (2025). Your town's ordinance and your lot decide the details, so we check both before design starts.
New Hampshire's default cap is 950 square feet, while Massachusetts caps a by-right ADU at 900 square feet or half the main house, whichever is smaller. A design sized for Massachusetts will usually fit New Hampshire, but a 950 square foot New Hampshire plan can be too big for a smaller Massachusetts home.
| Question | New Hampshire | Massachusetts |
|---|---|---|
| Allowed by right? | Yes, one ADU since July 1, 2025 | Yes, one ADU since February 2, 2025 |
| Detached allowed? | Yes | Yes |
| Size cap | 950 sq ft unless the town allows more | 900 sq ft or half the main home, whichever is smaller |
| Owner occupancy | Town may require it for one of the two units | Town cannot require it |
| Added parking | Up to one space | Up to one space, none near transit |
| Septic review | RSA 485-A:38 | Title 5 |
Septic deserves an early look on any lot with a private well and septic system. An added bedroom has to be supported by the system, and that can mean a new state septic approval before the building permit. We check the well, the septic design and the lot layout during feasibility, before design is final.
Each town applies RSA 674:72 through its own ordinance. These pages cover the local details where we build most often on the New Hampshire side:
Bradford ADUs start at $400 per square foot. The in-house designs are evolving starting points. Garages, site conditions, finishes and the agreed project scope affect the total; the stated living areas do not establish a complete project price. Pricing is cost-plus, with a detailed estimated not-to-exceed budget before construction begins. See what drives ADU cost.
You get daily photo updates from your job site, from the foundation and ICF walls through framing and finishes. You also have one accountable project manager, so when you have a question, you know exactly who to call.
Once permits are approved and site preparation is complete, ICF construction typically takes about one month. Wood-framed construction may take longer depending on project scope. The full process from initial consultation to move-in ready is usually 4-6 months, with permitting being the most variable factor.
Yes. You do not need a special permit for one ADU in Massachusetts or New Hampshire, but you still need a building permit and the trade permits that go with it. Bradford handles all permitting as part of our design-build process. See how the Massachusetts permit process works.
Since February 2, 2025, Massachusetts homeowners can build one ADU by right on a lot in any single-family zoning district. It can be up to 900 square feet or half the main house, whichever is smaller, and towns cannot require owner occupancy. The full Massachusetts rules are above.
Not by town rule. A Massachusetts town cannot require separate water, sewer or electric connections for an ADU, though a utility company or state requirement can. Septic capacity is often the deciding factor, since adding a bedroom can trigger a Title 5 review.
Both states let you choose. An attached ADU usually costs less to connect to utilities, and a detached ADU gives both households more privacy. We walk your lot with you and model both options before design starts.
In most communities, yes. ADUs can be used for long-term rentals, and some towns allow short-term rentals. Rental regulations vary by municipality.
An ADU is a separate, self-contained home with its own entrance, kitchen, and bathroom. A home addition expands your existing house. We build both, and the side-by-side comparison above shows which fits your goals.
Yes. Every Bradford ADU is customized to fit your property, needs, and preferences. We offer different configurations (detached, connected, above garage, attached), multiple exterior styles, layout modifications, and finish selections.
Yes. Bradford Construction Management is based in Plaistow, NH and is licensed and insured in Massachusetts and New Hampshire. We build ADUs across Southern New Hampshire and the Seacoast, including ADUs in Exeter and ADUs in Portsmouth, as well as the North Shore and Merrimack Valley.
Since July 1, 2025, New Hampshire towns must allow one ADU, attached or detached, as a matter of right wherever a single-family home is allowed. It can be up to 950 square feet unless the town allows more. The full New Hampshire rules are above.
Through Bradford Home Services (BHS), you have a permanent team for maintenance, repairs, and warranty work for as long as you own your home, so you always know who to call.
Custom Homes · Home Additions · ICF Construction · Home Renovations · Design-Build Services · View Projects · Finance Your Project
The best next step is a free consultation to discuss your property, your goals, and whether an ADU makes sense for your situation. Or download our lookbook with concept design views and pricing guidance.
Bradford Construction Management · 978-945-9771
Bradford ADUs are residential structures intended for independent living. They do not replace professional medical, nursing, or assisted-living services. If medical care is a consideration, please consult with healthcare professionals about your specific needs. ADUs can serve aging parents, adult children, guests, home offices, or generate rental income depending on local zoning regulations.
