BlackDog Builders offers full-service ADU design/build solutions, handling design, permitting, and construction under one roof. Specializing in detached ADUs, backyard cottages, in-law suites, and granny flats, they back projects with a 3-year warranty.
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Honorato Company offers a structured construction process in Boston, covering ADUs, garage conversions & renovations. From consultation to final walkthrough, they ensure transparency, permitting, design, and clear communication throughout.
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An Accessory Dwelling Unit (ADU) is a self-contained living space on a residential property. Massachusetts law now makes ADU construction easier. Aureli Construction offers full-service ADU building, from zoning research to completed construction.
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Mass ADU is a Massachusetts-based ADU contractor offering full-service accessory dwelling unit construction. Services include free consultations, permitting, design, and build. They serve homeowners statewide with a clear 3-step process.
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Sensible Home Solutions builds ADUs, in-law suites & secondary living spaces across Maine, Massachusetts & New Hampshire. Services include detached units, garage conversions & basement ADUs. Free discovery call available.
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Turkel Design offers custom-designed accessory dwelling units (ADUs) using a prefab process. Highlights include expert cabinetry, smart storage, and high-quality finishes, ensuring ADUs feel purposeful and cohesive with the main residence.
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Meetinghouse Builders offers custom ADU design & construction in Hollis, NH. Services include detached builds, garage conversions, basement ADUs & home additions. Features 3D renderings, style guides & full construction documents.
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ADUs are now legal statewide in Massachusetts. Atlantic Property Development builds custom Accessory Dwelling Units on the North Shore, offering design, permitting, and construction services for detached, attached, and garage conversion ADUs.
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FiveTen Construction & Design is a Massachusetts ADU contractor offering design, permitting, and construction services. They build detached, attached, basement, and garage ADUs, ensuring full compliance with MA building codes and zoning regulations.
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Top-Pro Construction, Inc. is Greater Boston's trusted ADU builder with 25 years of experience. Specializing in detached ADUs, attached units, garage conversions & basement ADUs to boost property value and rental income.
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SRH Homes builds custom ADUs, including 500 SF 1-bed and 800 SF 2-bed units. Options include high-end finishes and mini-split HVAC. Financing via HELOC or cash-out refinance. Ideal for rental units, granny flats, or in-law suites.
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At Hobart Contracting, we design and build high-quality Accessory Dwelling Units (ADUs) that fit your lifestyle and property. Whether you’re planning a guest house, in-law suite, rental unit, or private retreat, our team creates spaces that are functional, beautiful, and built to last.
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Allan Tran's Exterior Finish Work (AJT Properties) specializes in residential exterior services including deck construction, porch railing installation, storage structures, and CertainTeed siding. Known for reliable communication, on-budget delivery, and durable craftsmanship.
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North Shore ADU Home Builders LLC builds custom ADUs up to 900 sq ft across Massachusetts. Services cover design, permits & construction. Rental income ranges $1,800–$3,500/month. Property values may rise $100K–$250K.
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Kinstruct Tiny Homes is a Pacific Northwest contractor specializing in tiny homes and ADUs, including detached ADUs, backyard cottages, granny flats, and in-law suites built to maximize space and meet local codes.
read morePortsmouth, New Hampshire is one of the oldest cities in the United States, founded in 1623 along the Piscataqua River. This rich history means that many neighborhoods feature historic homes and protected districts, which creates unique challenges for ADU contractors working in the area. If you are considering adding an Accessory Dwelling Unit to your Portsmouth property, working with experienced local ADU contractors who understand the city's specific zoning codes, historic preservation guidelines, and building regulations is absolutely essential.
Portsmouth has made efforts to encourage ADU development as part of addressing the region's housing needs. Under Portsmouth's zoning ordinance, ADUs are permitted in most residential zones, including single-family and multi-family districts. However, there are important rules that your ADU contractor must navigate carefully:
A significant portion of Portsmouth's residential properties fall within or near designated historic districts, such as the Strawbery Banke neighborhood. ADU contractors working in these areas must obtain a Certificate of Approval from the Historic District Commission before construction can begin. This means that exterior materials, window styles, rooflines, and overall design must be compatible with the historic character of the surrounding neighborhood. Skilled ADU contractors in Portsmouth are familiar with these requirements and can help homeowners design units that satisfy both modern functionality and historic preservation standards.
Hiring a contractor with direct experience in Portsmouth is a significant advantage. Local ADU contractors understand the nuances of working with the Portsmouth Planning Department, the Building Division, and the Historic District Commission. They are also familiar with the city's infrastructure, including older utility connections and foundation types common in New England homes, which can affect ADU construction costs and timelines.
Whether you are planning a garage conversion, basement ADU, or a new detached backyard cottage, working with qualified ADU contractors in Portsmouth, NH ensures your project meets all local codes and historic guidelines while maximizing your investment.