ADU Construction Pricing in Seattle
ADU pricing in Seattle ranges from $180,000 for a garage conversion to over $700,000 for a custom two-story DADU. Here is exactly how we structure pricing across three tiers, what is included at each one, and the five line items that move the budget up or down.
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Quality. Precision. No surprises. Get a free estimate and start your home remodel and renovation with confidence today!
CHOOSE YOUR TIER
What to Expect from ADU Construction Pricing
Basic ADU
Garage, Basement, or Attached Conversions
The entry-point ADU. Almost always a garage conversion, basement conversion, or attached ADU that uses structure you already own. You skip the new foundation, which is the single biggest cost driver, and tie into your main home's existing utilities rather than running new lines from the street.
Garage conversions typically start around $180,000 to $220,000. Basement ADUs run $200,000 to $300,000 because of egress windows, ceiling height retrofits, and slab waterproofing. Best fit when the goal is rental income or multi-generational use without premium finishes.
What's Included
- Studio or one-bedroom layout, typically 400 to 700 sq ft
- LVP flooring, stock cabinetry, basic bath fixtures
- Functional kitchen with standard appliances
- One full bathroom
- Utility connections tied into the main home
- All permits, design, and engineering included
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Mid-Range Detached ADU
New Backyard Cottage with Full Foundation
Where most Seattle homeowners land. A brand-new detached backyard cottage, typically 500 to 800 sq ft, on a reasonably flat lot. You get a full new foundation, independent utility hookups, and real design flexibility. The unit stands alone, has its own address, and functions as a small house.
Detached ADUs in Seattle generally range $300,000 to $500,000 depending on size and design complexity. Premium neighborhoods like Capitol Hill, Madison Park, and Queen Anne typically push the floor toward the upper end of that range due to tighter lots and higher finish expectations.
What's Included
- New engineered foundation sized for your site
- Independent water, sewer, and electrical from the street
- Quartz countertops and upgraded cabinetry
- Higher ceilings (typically 9 ft) and upgraded windows
- Architectural character that complements the main home
- Full permitting and engineering managed by us
Custom High-End DADU
Two-Story Custom Architecture, Premium Finishes
Where Seattle's premium neighborhoods build. Custom architecture matching the main home, often two stories, with premium finishes throughout. Custom cabinetry, designer tile, high-end appliances, smart home wiring, and frequently a challenging site with slope, difficult soil, or significant tree protection.
Detached ADUs at this tier typically start around $500,000 and can exceed $700,000, especially in neighborhoods like Laurelhurst, Madison Park, Madrona, and View Ridge where homeowners build with the same architectural detail as the main home. A Tier 3 ADU is an investment in property identity, not just rental income.
What's Included
- Two-story layout with primary suite upstairs
- Custom cabinetry, designer tile, premium appliance packages
- Smart home integration and dedicated HVAC zones
- Site engineering for slope, soil, or tight access
- Architectural detail matching a high-end main home
- Full project management and one-year warranty
Flexible Payment Plans in Seattle
We make home renovations affordable with financing options that fit your budget, from small projects under $100k to major renovations over $100k. Start your project now!
SEATTLE ADU Projects – See Our Transformations
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How We Make Seattle Remodeling Easy
A Simple, Stress-Free Remodel Journey
Request an Initial Consultation
In person Consultation
Pre-construction Agreement
Construction Phase
Final Walkthrough & Warranty
Real Feedback, Real Transformations
Our Clients Love Their Home Remodels
Nothing speaks louder than real results. Our clients love the transformations we help bring to life, and their feedback reflects the quality, care, and craftsmanship behind every project. From home remodels to custom builds, see why homeowners trust Brutsky Builds to turn their vision into reality.
Irina S, on Yelp
Love working with Brutsky Builds kitchen and bathroom remodeling! They take immediate massive action and get things done. They did a lot of pre construction planning so that there was always work going on our project. They completed everything on time and excellent quality.
Kyla Regan, GOOGLE REVIEWS
We hired Brutsky Builds to help us build the Primary bathroom of our dreams. We required extensive repairs due to water damage in the space, and Erik's Team tackled it all. They guys replumbed the space, installed a new dedicated hot water heater, installed drywall, a new shower, new tub, new vanity, etc. Our Primary bathroom looks fantastic! Erik's team is professional, knowledgeable, talented, and courteous. They came in when we needed Professional help and worked their magic. We are incredibly pleased and very grateful.
Sunyoung H, GOOGLE
We recently finished an amazing master bathroom remodel with Brutsky Builds. Erik, Filip, and his crew are dedicated, professional, and dependable. During the initial planning meeting, they provided a useful tool to help us plan out the remodel and keep the project on track. Filip was a great project manager who provided daily updates with pictures and was super responsive to all my concerns and questions. The paid attention to every detail, ensuring everything was perfect. The entire process was smooth, and the final result is a beautiful and functional space we absolutely love. Don't let their seeming 'youth' fool you- These guys know what they're doing! We highly recommend Brutsky Builds for any home renovation projects.
Vadim P, on Yelp
Since we had little experience in construction, we were very hesitant to take on a big full home remodeling project. Especially after hearing so many horror stories from other's. So we were carefully interviewing and choosing a contractor. We chose Erik's team at Brutsky Builds because of their honesty and ease of communication and flexibility we saw. These guys/gals are truly dedicated to excellence and clearly passionate for their work (every member on the team). We had an incredible experience remodeling our home with Brutsky Builds.
Kelly A, Facebook
4. Brutsky Builds recently completed our kitchen remodel and they exceeded our expectations. This is our third remodel on our 1955 mid-century home - first with Brutsky Builds - and this was our easiest and smoothest remodel.
The team did a complete demo of our kitchen, taking it down to the studs. From there, they patched our original wood flooring, tore down a wall and an archway, did new insulation, dry walled, relocated most appliances, shifted our heating vent, hung (heavy) floating shelves, and then did the electrical, plumbing, cabinets, countertops, and tile.
All of this was completed in just 30 days. It was wild. And it’s GORGEOUS!! Everything turned out beautiful and we couldn’t be happier.
Matt B, GOOGLE
We had a challenging little project that Brutsky Builds made simple! We had a floating shelf made for between two cabinets in our bathroom, but our previous contractor made errors in the measurements, and it was the wrong size. After we moved on from him, Brutsky was willing to measure and recut the marble and then install it, for a reasonable price. Very pleased.
How ADU Pricing varies Across Seattle
ADU pricing in Seattle is not one flat number. The same 700 sq ft DADU that prices at $420,000 in Ballard might cost $475,000 in Madison Park. Same plan, same footprint, different math driven by lot character, tree protection, and site access.
Standard Seattle Lots
Neighborhoods like Ballard, Greenwood, Beacon Hill, and West Seattle. Flatter lots, easier access for equipment, fewer protected trees. Tier 2 DADUs land in the $350K to $450K range. The city's pre-approved DADU program works especially well here and can shave weeks off permitting.
Premium Seattle Neighborhoods
Laurelhurst, Madison Park, Madrona, Queen Anne, and View Ridge. Tighter lots, mature tree protection, stricter design expectations, and higher finish levels. Expect Tier 2 and Tier 3 numbers at or above the top of the range, with most builds starting near $500K.
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Why Seattle Homeowners Choose Brutsky Builds for ADU Construction
Building an ADU is a major investment, and the right builder can make the entire experience smoother from planning to final construction. At Brutsky Builds, we focus on creating well-designed, functional ADUs that match your property, goals, and long term needs.
✔ Full-Service ADU Design & Construction
Our team manages the entire ADU construction process, helping homeowners avoid the hassle of coordinating multiple contractors and vendors. From early planning through final finishes, we keep the project organized and moving forward.
- Custom ADU layouts designed around your property and lifestyle
- Durable materials and finishes selected for long term performance
- Energy-efficient construction options for comfort and lower utility costs
- Detached ADUs, backyard cottages, and garage conversion solutions
✔ Local ADU Experience That Matters
Seattle ADU projects involve zoning requirements, permits, utility coordination, and detailed planning. Our local experience helps streamline the process and reduce common delays.
- Licensed and experienced Seattle ADU construction team
- Familiar with local zoning, permitting, and code requirements
- Quality craftsmanship with attention to detail throughout the build
- Clear communication and realistic project expectations
✔ Built for Real Life
Whether you are building an ADU for rental income, multigenerational living, guest space, or a private home office, we design spaces that feel connected to your property and practical for everyday use.
At Brutsky Builds, we focus on thoughtful construction, efficient layouts, and lasting value so your ADU works well now and for years to come.
Start Your Seattle ADU Project With Brutsky Builds
If you are planning an accessory dwelling unit in Seattle, our team is ready to help you explore design options, construction costs, and the next steps for your property.
FAQs About ADU Construction in SEATTLE
Please feel free to call. But here are some frequently asked questions we get.
A basic ADU in Seattle runs between $180,000 and $320,000. That range covers garage conversions, basement conversions, and attached ADUs that reuse an existing foundation and tie into the main home's utilities. New detached construction starts higher.
A garage conversion is typically the cheapest, starting around $180,000 in Seattle. You skip the new foundation, most utility trenching, and a chunk of the structural framing that drives up new construction pricing.
ADU pricing in Seattle varies because of lot character, tree protection, site access, and finish level expectations by neighborhood. A 700 sq ft DADU in Ballard or Greenwood typically prices around $420,000, while the same plan in Laurelhurst or Madison Park can land closer to $475,000 due to tighter lots, mature tree protection, and higher finish expectations.
Our quotes include permits, design, engineering, and all soft costs. Many contractors quote construction only and add design and permits separately, which is how a $300,000 estimate becomes a $380,000 final bill. Always ask whether a contractor's number is all-inclusive before signing.
Tier 1 garage conversions typically run 4 to 6 months from permit approval. Tier 2 detached ADUs average 6 to 8 months of construction. Tier 3 custom builds usually take 8 to 12 months. Design and permitting add another 3 to 6 months on top, so total timelines from first meeting to move-in run 9 to 18 months.
Watch for utility trenching through hardscape, geotech reports on sloped lots, tree protection plans, the King County sewer capacity charge billed over 15 years, and change orders from scope creep during design. A solid pre-construction agreement catches most of these before they hit you mid-build.
Start Your SEATTLE ADU Construction Journey Today
Need more space? Our Seattle ADU construction team makes it easy—smart designs, no stress, and built just for you. Let’s talk!
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