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Indoor-outdoor coastal living room with ocean view in La Jolla
ADU Construction · KING, PIERCE & KITSAP COUNTIES

Best ADU Construction for Modern Living.

A well-designed accessory dwelling unit is a second home, a rental, an in-law suite, or all three, depending on the season. Pacific Blue Design & Build provides ADU construction across King County, Pierce County, and Kitsap County, with a design-build approach that handles site planning, permitting, and construction under one clear process.

Licensed & Insured Locally Based Design-Build Experts
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ADU Construction

An ADU That Fits Your Lot, Your Life, and Seattle Code.

An accessory dwelling unit is one of the most personal projects a homeowner takes on. It might house a parent, a college-aged child, a long-term tenant, or a future version of yourself. The design needs to anticipate years of use, not just the first one. Pacific Blue Design & Build approaches every ADU construction project in Seattle with that long arc in mind, planning for accessibility, privacy, sound, and storage from the first sketch.

This is not a packaged backyard cottage. It is a design-build approach for homeowners across the Puget Sound who want a true second residence on their property. Whether you are building a detached ADU in the backyard, a garage conversion, or an attached basement unit, our goal is the same: a small home that lives well, meets current Seattle DADU code, and adds lasting value to the property.

Intricate architectural details and millwork
Flawless flooring transitions in a remodeled space

ADU Construction Services

ADU Projects We Take On for Pacific Northwest Homes.

Every property has different ADU possibilities depending on lot size, setbacks, existing structures, and zoning. Pacific Blue Design & Build reviews each site individually and designs an ADU that fits the property rather than forcing the property to fit a plan.

OUR 3D DESIGN-BUILD PROCESS

See Your Remodel Before We Build It.

Remodeling decisions get expensive fast when you can't visualize the outcome. Our 3D design-build process removes the guesswork: every wall, finish, fixture, and sightline is modeled before construction begins. You'll walk through your remodel in photorealistic detail, make confident choices early, and avoid the costly change orders that derail most projects.

After: structurally remodeled great room with vaulted ceiling and indoor-outdoor flow
Before: original interior, prior to structural and finish remodel
Before · Demolition After · Reveal
Architectural blueprint and craftsmanship details

Pacific Northwest Design-Build

Elevating the Standard of Local Remodeling.

Pacific Blue Design & Build was created for homeowners who want more than a basic remodel. The process should feel organized. Communication should feel clear. The design should feel connected to the home and the way people live throughout the Pacific Northwest. We serve homeowners across King County, Pierce County, and Kitsap County with a thoughtful, design-focused approach that values functionality, timeless materials, natural flow, and careful planning.

  • Fixed-price contract, locked before construction begins
  • Written completion date, with per-diem accommodation guarantee
  • Two-year comprehensive workmanship warranty
  • Direct principal oversight, every commission, no exceptions
  • All permits pulled and inspections submitted in client's name
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Complementary Services

Built to Work Together.

An ADU project often touches the main home and the outdoor space around it. Explore the services that most often pair with ADU construction.

Bespoke kitchen with Calacatta island and European oak cabinetry — 01

Room Additions

When the ADU plan is best handled as an attached unit, a thoughtful addition can deliver the same square footage with a different feel.

Explore Service
Spa-inspired primary bath with bookmatched stone and curbless wet-room — 02

Basement Remodeling

A finished basement can serve as the foundation for an attached ADU, with proper egress, ventilation, and code compliance built in from the start.

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Architectural plans and 3D renderings produced in-studio — 03

Hardscaping

A detached ADU benefits from a clear, well-designed path, patio, and outdoor zone that ties it to the main home and the property as a whole.

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Exterior pergola, loggia, outdoor kitchen and pool deck integration — 04

Deck Construction

A small deck or terrace gives an ADU its own outdoor moment, which makes the unit feel like a true home rather than a guest room.

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The Practice
"I built this practice around the way I'd want a contractor to treat my own home — fewer clients, more oversight, and decisions made in writing before work begins. That's the standard on every Shiro commission."
— Shir Gal Founder & Principal

Our Remodeling Process

From First Conversation to Final Walkthrough.

Remodeling should not feel like guesswork. Our process is built to help Seattle homeowners move from early ideas to a more defined plan with fewer surprises and better decisions along the way.

Architectural blueprint and craftsmanship details
— 01

Discovery & Consultation

Every project starts with a conversation in your home. We listen closely, take careful measurements, and learn what matters most, from the way you use each space to the realities of your budget.

— 02

Site Review & Design Direction

Our in-house architect shapes your vision into a tailored design, paired with curated material samples, photorealistic walkthroughs, and a clear, itemized estimate so nothing is left to guesswork.

— 03

Construction Coordination

A dedicated project manager leads construction from start to finish, with weekly on-site walkthroughs and a private client portal that keeps you informed at every stage.

— 04

Final Walkthrough

We finish the way we started, with care. Your home is professionally cleaned, every system tested and commissioned, and a complete maintenance binder handed over alongside photos documenting the journey from day one.

Start With a Clear Plan

Ready to Plan Your ADU Construction?

If you are exploring an ADU for rental income, family use, or long-term flexibility, start with a team that takes design, code, and craft seriously. Pacific Blue Design & Build helps homeowners across King, Pierce, and Kitsap counties plan, permit, and build accessory dwelling units that hold their value.

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Architectural blueprint and craftsmanship details

Frequently Asked Questions

ADU Construction: Common Questions.

We've gathered the most common questions homeowners ask us, so you can plan your remodel with clarity and confidence.

What is the difference between an ADU and a DADU?

An ADU is any accessory dwelling unit, including ones attached to the main home. A DADU is a detached accessory dwelling unit, meaning a standalone structure on the same lot. Seattle allows both, with different rules around size, height, setbacks, and parking depending on the property.

Can I build an ADU on my Seattle lot?

Most single-family lots in Seattle, King County, Pierce County, and Kitsap County allow some form of ADU. The specifics depend on lot size, zoning, setbacks, and existing structures. We review your property and the current code during the design phase to confirm what is possible.

How long does ADU construction take?

A detached ADU typically takes 8 to 14 months from initial design through final inspection, including permitting. An attached ADU or garage conversion often runs shorter, depending on how much of the existing structure is reused. We provide a written timeline once the scope is defined.

Do you handle ADU permitting?

Yes. We handle full permitting through Seattle DCI, King County, Pierce County, or Kitsap County, including land use review, structural review, and Washington State Energy Code compliance. You sign nothing at the city counter.

What is the typical size of a Seattle ADU?

DADUs in Seattle are generally capped at 1,000 square feet of conditioned space, with some flexibility depending on zoning and lot conditions. Attached ADUs often run between 500 and 1,000 square feet. We design to fit the way you intend to use the unit, not just to the maximum size.

Pacific Blue Luxury Home Remodeling

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