DADU Architect

The DADU architect.

A black and white image of a custom home residence

At Refine Design Architecture, we are your starting point for any DADU project—guiding you from first sketch through construction. As licensed residential architects in Washington, we collaborate closely to craft thoughtful detached accessory dwelling units that meet local permitting requirements and maximize your property's potential. Our work goes beyond drawings: we choreograph light, views, and circulation to create memorable architectural moments that make you pause, reflect, and connect with your space. Whether you're seeking rental income, multigenerational living, or a flexible home office, our high-caliber design, detailed documentation, and personalized service shape DADUs your family will cherish for generations.

Meet our Residential Architect Team

What can we do for you?

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01. Pre-Design

This is where we get on a first name basis. Our team of architects collaborates with you to understand your DADU vision and goals, verifying zoning requirements and setback restrictions for your property.

02. Design

This is the good stuff. With your ideas and our design expertise, our team puts together several DADU design options, exploring efficient floor plans and 3D renderings of your accessory dwelling unit.

03. Permits

At this point, your DADU design is ready for local jurisdiction submission to obtain necessary building permits. We can lead this effort, or assist you in navigating the permitting process.

04. Construction

Lastly, we provide you with construction drawings detailed to a level that can be given to a general contractor to start building your DADU! We help vet builders and coordinate throughout construction to keep your project aligned.

Don't just take our word for it.

Here's what our clients have to say.

"RD's team provided us with a very special creative process designing our home...If you are seriously looking to elevate your next project, work with Refine Design!"

Shy F.

Mountain Lodge

"Stone and Julia were very professional and extremely helpful in designing our project. Their patience and attention to detail were integral in configuring a change of use building."

Dustin D.

Ballard DADU

"They not only helped bring our vision to life, but offered a point of view we had not thought of. I highly recommend this duo - they are incredibly easy to work with."

Kendall F.

Gig Harbor Remodel

"No words can describe how exceptional Julia and Stone are at their work...Not only did they research extensively into the building codes but they poured so much thought into the design."

Yu Chi S.

Seattle Bathroom Remodel

"It was great working with Refine Design Architecture for our cabin expansion. They listened to our requirements, offered feedback and produced designs that fulfilled our vision"

Antonio G.

Leavenworth Cabin Addition

"Their work was on schedule, on budget, and their ideas were very helpful. If you're searching for an architectural team that can fit the bill, look no further."

James M.

Accessibility Retrofit

Have questions?
We have answers.

At Refine Design Architecture, we believe that designing a DADU isn't a "one size fits all" process.

What is the DADU design process?

Our DADU process follows a clear path: idea generation and site analysis → design development → secure funding → permit submission → find a qualified builder and start construction. We begin by understanding your goals for the space, whether it's rental income, aging-in-place solutions, or flexible living arrangements. Each phase builds thoughtfully on the last, ensuring your DADU meets both your family's needs and local requirements. Our team guides you through every step, from initial feasibility through construction completion.

Do I need a licensed architect for my DADU?

In Washington State, a licensed architect isn't always required for DADU projects, but is highly recommended for most builds. Many jurisdictions have specific DADU requirements around setbacks, height limits, and design standards that benefit from professional expertise. An architect ensures your project meets all local codes while maximizing your investment. We navigate the complex permitting landscape so you can focus on your vision for the space.

What does DADU construction cost?

DADU construction costs vary widely based on size, complexity, site conditions, and material selections. Factors like existing utilities, site accessibility, and local building requirements all influence pricing. A basic DADU typically costs less per square foot than a custom home, but premium finishes and complex designs increase investment. We help you understand cost implications during the design phase, so you can make informed decisions that align with your budget and goals.

How long does a DADU project take?

DADU design typically takes 2-4 months, depending on project complexity and revision cycles. Permitting timelines vary by jurisdiction but generally range from 2-6 months for DADU projects. Construction duration depends on size and complexity, typically 6-12 months for most accessory dwelling units. Weather, material availability, and contractor scheduling can affect timelines, but we work closely with you to set realistic expectations and keep your project moving forward efficiently.

How much does a DADU architect cost?

DADU architect fees typically range from 8-15% of construction cost for full-service residential projects. We also offer hourly consultation and fixed-fee arrangements for specific project phases. Our fee structure reflects the scope of services needed, from basic permit drawings to full design and construction administration. The investment in quality architectural services often pays for itself through efficient design, smoother permitting, and avoided construction issues.

Why hire an architect for your DADU?

Our DADU expertise goes beyond code compliance to create spaces that truly enhance your property and lifestyle. We understand local zoning intricacies, design for maximum rental potential, and create thoughtful connections between your main home and accessory unit. Our team brings creative problem-solving to challenging sites and tight budgets, ensuring your DADU feels intentional and well-crafted. The result is an accessory dwelling unit that adds lasting value to your property while serving your family's evolving needs.