Looking to add an accessory dwelling unit? These five US builders bring different strengths to the table, from custom design to full-service remodeling.
The ADU Landscape in 2026
Accessory dwelling units have become a go-to solution for homeowners seeking extra space, rental income, or multi-generational living. As zoning laws loosen across the country, more builders are offering specialized ADU services, from detached units to garage conversions. The market now includes everything from design-build firms to full-service remodelers who handle kitchens and bathrooms alongside ADUs. For you, the challenge is finding a contractor who matches your project's scope, budget, and local regulations. This roundup highlights five companies that stand out for their service depth, craftsmanship, and client focus.
How We Evaluated These Builders
We looked at each company's service scope, pricing transparency, local expertise, and customer experience. For service scope, we considered whether they offer design, permitting, and construction in-house. Pricing clarity was assessed by how openly they communicate costs and packages. Local fit mattered for understanding regional zoning and building codes. Finally, we weighed the overall client journey, from first consultation to final walkthrough.
Here's a quick snapshot of the five ADU builders, their specialties, and what they're best for.
| Provider | Best For |
|---|---|
| Haas Development & Construction | Seattle homeowners seeking custom or prefab ADU expertise |
| Home - GoPro Remodeling Inc. | Homeowners wanting a full-service remodeling partner for ADUs and more |
| Greater Seattle Remodeling | Seattle-area homeowners who value transparent pricing and design-build services |
| Deane Home Services | South King County homeowners wanting custom, code-compliant ADUs |
| Green Bay Remodeling | Homeowners in Texas and the Bay Area seeking a one-stop ADU builder |
Detailed Look at Each Builder
#1 Haas Development & Construction
A screenshot of the Haas Development & Construction website.
Haas Development & Construction specializes in ADU and DADU projects across the Greater Seattle area, offering both prefab and custom-designed solutions. They guide you through planning, design, engineering, and construction, with pre-approved plans to speed up the process. Their team is dedicated to realizing your vision, whether you need an attached or detached unit. If you're in Seattle, their local expertise is a major plus. Check out their project gallery to see their range. They're a solid choice for homeowners who want a dedicated ADU specialist.
#2 Home - GoPro Remodeling Inc.
A screenshot of the Home - GoPro Remodeling Inc. website.
GoPro Remodeling Inc. brings over 20 years of experience to home remodeling, including ADU construction, kitchen and bathroom remodels, and patio covers. They position themselves as a one-stop shop, managing every step from consultation to final walkthrough. Their focus on quality craftsmanship and clear communication makes them a reliable partner for transforming your home. They tailor solutions to your vision, needs, and budget, ensuring a personalized experience. If you're planning an ADU alongside other home upgrades, their full-service approach is a strong fit. They offer free consultations to get you started.
#3 Greater Seattle Remodeling
A screenshot of the Greater Seattle Remodeling website.
Greater Seattle Remodeling offers ADU construction as part of a broader remodeling portfolio, including kitchens, bathrooms, and whole-house renovations. They provide vetted contractors and transparent project pricing, with ADU projects starting at $150,000. Their process includes permit processing, 3D design plans, and architectural and engineering services. They emphasize a fast, fair comparison of builders, making it easy for you to get started. If you're in the Seattle area and want a single company for multiple projects, they're worth considering. Their customer service focus aims to exceed your expectations.
#4 Deane Home Services
A screenshot of the Deane Home Services website.
Deane Home Services specializes in custom ADU design and construction in South King County, Washington. They focus on maximizing your property's value with structures that blend seamlessly with your existing home. Their services include garage conversions, attached ADUs, and basement remodels, all tailored to your lot's unique constraints. They emphasize smart design and expert craftsmanship, whether you need a rental unit or a private space for family. Their approach is anything but cookie-cutter, bringing custom home quality to the backyard. If you're in South King County, they're a strong local option.
#5 Green Bay Remodeling
A screenshot of the Green Bay Remodeling website.
Green Bay Remodeling offers ADU construction across Texas and the Bay Area, with a focus on custom solutions for guest houses, rental units, or home offices. They position themselves as a one-stop shop, handling everything from design to build. Their design-build approach ensures your ADU is crafted with precision and quality materials. They also offer discounts on ADUs, making them a budget-conscious choice. If you're in their service areas and want a hassle-free process, they're a solid pick. Their team is dedicated to making your ADU project stress-free.
How to Choose the Right ADU Builder for You
Start by defining your project's scope—are you building a detached ADU, converting a garage, or adding a basement unit? Consider your budget and whether you need design and permitting help. Look for a builder with local experience, as zoning and codes vary widely. Check their portfolio and client reviews to gauge craftsmanship and reliability. Finally, get multiple quotes and compare what's included, from materials to project management. The right fit is one that aligns with your goals and makes you feel confident.
Streamlining Your ADU Project with Automation
Modern ADU builders are using automation to simplify the process. From online consultation scheduling to 3D design tools, you can now visualize your project before breaking ground. Some companies offer digital project tracking, so you can monitor progress in real time. Automated permit filing and document management reduce delays. When comparing builders, ask about their use of technology to keep your project on time and on budget.
Final Thoughts
Choosing the right ADU builder comes down to your specific needs and location. Whether you prioritize local expertise, full-service remodeling, or budget-friendly options, these five companies offer something valuable. Take the time to research each one, request consultations, and find the partner that feels right for your home. With the right team, your ADU can add space, value, and comfort to your property.