ACCESSORY DWELLING UNIT (ADU) BUILDER in Central NH
Accessory Dwelling Units (ADUs) are a smart, flexible solution for New Hampshire homeowners who want more from their property. Whether a guest suite, multigenerational living space, or income-generating property, ADUs offer a thoughtful and affordable way to expand how your home works.
Attached ADUs
Detached ADUs
In-Law Apartments
Guest Suite Additions
Backyard Cottages
Carriage Houses
Garage Conversion ADUs
Income-Producing ADUs
affordable ADU housing
Combining smart, efficient design, we use a cost-conscious approach to ADU construction. The result is an affordable, customized living space that is built to last. Ideal for an in-law apartment or backyard guest house, an ADU lets you add the living space you need without disrupting daily life in your primary home.
ADU CONSTRUCTION FOR MODERN LIVING
Today’s homeowners are more intentional about design and function. It’s no longer just about adding more square footage; it’s about creating a living space that truly works for modern, everyday life and evolves with your changing needs.
net zero ADU living
Engineered for next-generation performance, every ADU we build is Net Zero-ready, with the option to operate entirely fossil fuel-free. Designed with building science in mind, we use a thicker wall assembly with exterior insulation to reduce heat loss, improve indoor comfort, and lower energy bills. It’s a smart, forward-thinking foundation for sustainable living.
*A net-zero home is a highly energy-efficient house that generates as much renewable energy as it uses annually through advanced construction, efficient systems, and on-site power like solar.
Custom ADU Design & Construction
The core structure of your ADU is thoughtfully engineered, and every element is customizable—from the roofline and room layouts to the materials and exterior aesthetics. This allows you to get the functionality, look, and feel you need to make your living space uniquely yours.
NH ADU FAQs
An Accessory Dwelling Unit (ADU) is a secondary living space on your property — a complete, self-contained unit with its own kitchen, bathroom, and entry. ADUs are flexible solutions that add value, increase usability, and expand your home’s potential without the complexity of a full addition. From backyard cottages to garage conversions, we help you unlock the possibilities.
Yes. New Hampshire state law (RSA 674:71–73) requires municipalities to allow at least one ADU on any single-family lot in most zoning districts. Towns can regulate size, placement, and design, but they generally cannot prohibit ADUs outright. Our design-build team will ensure you are in compliance with local regulations.
Usually, no variance is required if the ADU complies with local zoning rules. Most ADUs are approved through a zoning compliance review and building permit. A variance is only needed if you want to exceed local limits (such as size, setbacks, or height).
All work must comply with the New Hampshire State Building Code, and the following permits are required:
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Zoning approval or zoning compliance letter
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Building permit
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Electrical permit
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Plumbing permit
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Septic approval (if not on public sewer)
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Possibly driveway or fire access approval
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That depends on where you live. New Hampshire law allows attached or detached ADUs, but some municipalities only allow internal or attached units. Detached ADUs are becoming more common, but must be approved locally.
State law allows municipalities to limit ADUs to 750–1,000 square feet or a percentage of the primary dwelling (often 30–50%). Many New Hampshire towns cap ADUs at 750 sq ft or one bedroom, but this varies by town.
Yes, long-term rentals are generally allowed. However, many towns restrict short-term rentals (Airbnb/VRBO) or prohibit them entirely. Owner-occupancy of either the main home or ADU is often required.
Typically, no. Most ADUs share utilities with the main house. Some towns or utilities may require separate metering for detached units, but this is not common in New Hampshire.
If your primary home has a septic system, it must be designed or upgraded to handle the additional bedroom(s). New Hampshire DES requires septic capacity to match the total bedroom count, not the number of units.
Often, yes. New Hampshire towns commonly require one additional off-street parking space for the ADU, but some towns waive this requirement under certain conditions.
Your property will be reassessed based on the added living space, but ADUs typically increase its overall value more than taxes proportionally.
Yes! As a qualified ADU builder, we will coordinate with your town and prepare permit applications, working with any third-party professionals as needed.
