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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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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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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All City Remodeling Co. offers ADU construction, period molding installation, and beam ceiling paneling in Boston, MA, and North Shore communities including Hamilton, Salem, and Manchester-by-the-Sea.
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Landform Build is a Portland, Maine design-build firm specializing in infill development, ADUs, and residential projects. Services include zoning analysis, architectural design, feasibility studies, permitting support, and general contracting for accessory dwelling units and multi-family housing.
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River City Construction is a Boston-based ADU contractor specializing in home additions, garage conversions, in-law suites & detached backyard cottages. They manage design, permitting & full construction under one roof.
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Canbury Homes is a Maine-based modular ADU builder offering diverse floor plans like Columbia II, Clinton, Cameron, and more. They guide homeowners through Maine's ADU regulations, providing customizable, affordable accessory dwelling units.
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Alcantara Construction is an experienced ADU contractor specializing in detached ADUs, garage conversions, JADUs, in-law suites, and granny flats. They guide homeowners through planning, permitting, and building accessory dwelling units efficiently.
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T&J Builders specializes in custom ADUs in Dover NH, Portsmouth NH, NH Seacoast, Lakes Region & Southern Maine. Services include garage conversions, in-law suites & detached cottages for rental income, multigenerational living & added property value.
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Stella Home Services is a Greater Boston ADU contractor specializing in basement apartments, garage conversions, in-law suites & home additions. They manage design, permitting & construction for fully functional accessory dwelling units.
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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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Trust Contractors designs and builds ADUs, including detached units, garage conversions, basement ADUs, and in-law suites. Services cover zoning, permits, and construction, helping homeowners add rental income, family housing, or flexible living space.
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Bradford Construction Management brings commercial-grade project management to every ADU we build across the North Shore. That means daily photo documentation so you always know what's happening on site, transparent pricing so there are no budget surprises, and a clear schedule with real milestones.
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Millbrook Construction Corp. in Boston specializes in ADU construction, handling design, permits, and builds. Services include detached ADUs, garage conversions, and in-law suites for rental income, family housing, or added property value.
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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.
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.