ADU & DADU Contractor — King County, WA

Add a Legal Dwelling Unit
to Your King County Property

From permit application to final walkthrough — Prolific handles design-build ADU and DADU projects across Federal Way, Issaquah, Renton, Kent, and greater King County.

Get a Free ADU Estimate (425) 800-4775
$180KAverage ADU Cost (King County)
6–12moTypical Timeline Permit to Move-In
$1,800+Monthly Rental Income Potential
3–5yrAverage ROI Payback Period

What We Build

Every ADU project is custom-designed for your lot, your goals, and King County code.

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Detached ADU (DADU)

A standalone dwelling in your backyard. Most flexible for rental or multigenerational living. Requires setback compliance and separate utility connections.

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Attached ADU

Connected to the primary home via a shared wall. Lower cost than detached, faster permitting. Ideal for in-law suites or long-term rental income.

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Junior ADU (JADU)

Converted from existing interior space — garage, basement, or bonus room. Lowest cost entry point. Limited to 500 sq ft per King County code.

The King County Permitting Process

Prolific handles every step. Most homeowners have never pulled a permit — we've done hundreds.

1

Site & Zoning Review

We verify your parcel's zoning, setbacks, lot coverage, and utility capacity before design starts. Catches 80% of project-killers on day one.

2

Design & Engineering

Architectural plans drawn to King County standards. Structural engineering included where required. Typical design phase: 3–6 weeks.

3

Permit Submission

We submit to King County DPER or the applicable city (Federal Way, Renton, Issaquah, Kent). Electronic submission with full plan set.

4

Review & Corrections

County review typically takes 6–12 weeks. We respond to all correction requests and manage the back-and-forth until permit issuance.

5

Build & Final Inspection

Construction with milestone inspections. Final inspection and certificate of occupancy required before the unit can be rented or occupied.

Cost Ranges for King County ADUs

Rough estimates — every project varies by site, size, and finish level. Free estimate available after a site visit.

ADU TypeSize RangeTypical Cost Range
Junior ADU (JADU)Up to 500 sq ft$60,000 – $120,000
Attached ADU400–800 sq ft$120,000 – $200,000
Detached ADU (DADU)400–1,200 sq ft$160,000 – $320,000

Ready to Add a Unit to Your Property?

Free site consultation. We'll tell you what's possible on your lot before you spend a dollar.

Get Your Free ADU Estimate

Prolific's Differentiator

While We're Restoring Your Home, Let's Make It Better Than Before

Most contractors patch the damage and leave. We use the restoration as a launchpad — pairing insurance coverage with a remodel that upgrades what you had.

Storm + Remodel

Federal Way — Hail Damage + Kitchen Upgrade

Insurance covered the roof and siding. While we had the crew on-site, the homeowners financed a kitchen remodel they'd been putting off for years. One mobilization, two wins.

Water + Addition

Renton — Burst Pipe + Primary Bath Expansion

A burst pipe triggered an insurance claim for the subfloor and drywall. We rebuilt the bathroom larger than it was — same timeline, carrier paid the base, owner paid the delta.

Fire + Rebuild

Issaquah — Garage Fire + ADU Conversion

Garage total loss became a permitted two-car garage with a studio ADU above. Insurance rebuilt what burned. The ADU now generates rental income to offset the mortgage.

Tell Us What Happened — We'll Show You What's Possible
Insurance Claim? We Handle Everything.

Your Insurance Company Has Adjusters.
Now You Have Us.

STORM DAMAGE RESPONSEthousands more for homeowners just like you.

GET YOUR FREE CLAIM REVIEW → 📞 (425) 800-4775

Licensed & Insured · PROLISN776L6 · Serving All of King County

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Design & Remodeling Issaquah WA

Restoration Issaquah WA

General Contractor & Restoration Services in Issaquah, WA

As an Issaquah-based company, Prolific Design-Build and Restoration understands the unique challenges homeowners face in our foothill community. Nestled between Tiger Mountain and the Sammamish Plateau, Issaquah properties are exposed to heavy rainfall, snowmelt runoff, and the occasional windstorm that can cause unexpected damage to your home.

Whether you own a newer build in Issaquah Highlands, a classic home near historic Front Street, or a property along the Issaquah-Hobart corridor, our team has the local expertise to handle everything from emergency water extraction to complete kitchen and bathroom remodels. We know Issaquah because we live and work here every day.

Our Services in Issaquah

  • Water Damage Restoration & Emergency Flood Response
  • Fire & Smoke Damage Restoration
  • Mold Remediation & Prevention
  • Kitchen Remodeling & Custom Design
  • Bathroom Renovation
  • Home Additions & ADUs
  • Insurance Restoration Claims
  • General Contracting

Ready to start your project in Issaquah? Call us at (425) 800-4775 or request a free estimate today. As your neighbors, we treat every Issaquah home like our own.

Restoration & Roofing Contractor in Issaquah WA

Professional Roofing & Restoration Services in Issaquah, Washington

We’re proud to serve Issaquah and the surrounding foothill communities with comprehensive roofing, restoration, and exterior repair services. Issaquah’s location at the foothills of the Cascade Range exposes homes to significant weather challenges—heavy rains, sudden storms, and occasional severe hail and wind events that can damage roofs, siding, and exteriors. When disaster strikes, you need a trusted local contractor who understands Issaquah’s specific weather patterns and responds quickly. Our team has helped hundreds of Issaquah homeowners recover from storm damage, replace aging roofs, and restore their properties to excellent condition.

The Issaquah area’s combination of elevation, tree cover, and weather patterns creates unique maintenance needs. Your roof faces moisture accumulation, debris from surrounding trees, and impact from severe weather events. We understand these challenges because we live and work in this community. We provide rapid response to emergency damage, expert insurance claim documentation and support, and professional repairs that meet Issaquah building codes and protect your home for decades.

Services Available in Issaquah:

We offer a complete range of construction and restoration services to Issaquah property owners, including:

  • Roofing: Storm damage repair, roof replacement, leak detection, and professional installation of all roof types
  • Insurance Restoration: Hail damage, wind damage, water damage assessment and restoration with insurance claim support
  • Exterior Painting: Residential and commercial exterior painting for Issaquah homes and businesses
  • Siding Services: Vinyl siding, fiber cement, and siding replacement for storm-damaged and aging exteriors
  • Concrete Work: Driveways, patios, walkways, and foundation repairs in Issaquah
  • Drywall Services: Installation, repair, and water damage restoration for Issaquah homes
  • Pressure Washing: House exterior cleaning, driveway restoration, and roof cleaning for Issaquah properties

Why Issaquah Residents Choose Prolific Design-Build and Restoration

We’re local. We understand Issaquah’s neighborhoods, weather patterns, building standards, and the expectations of Issaquah homeowners. When you work with us, you’re not calling a distant contractor—you’re working with team members who live and work in your community. We respond quickly to emergency calls, communicate clearly throughout projects, and take pride in delivering excellent work that becomes part of Issaquah’s landscape. Many of our best customers are Issaquah residents who refer us to their friends and neighbors because they trust us.

Experiencing storm damage in Issaquah? Need a new roof, exterior repairs, or restoration? Call or text Prolific Design-Build and Restoration immediately: (425) 800-4775. We’re available 24/7 for emergency response. Contact us online for a prompt assessment and estimate.

Commitment to Excellence

At Prolific Design-Build and Restoration, our background in the industry, combined with our mission-driven approach, sets us apart. Our team of dedicated professionals brings extensive experience and a passion for excellence to every project. We prioritize client satisfaction and believe in transparent, collaborative relationships.

Free Estimate

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Dealing with storm damage? We're here — call now or submit your info and we'll call you within the hour.

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We Got Your Request

We respond within 2 business hours — same day for emergencies.

A member of our team will reach out shortly to schedule your free estimate or inspection. Here's what to have ready when we call:

What to Have Ready

  • Photos of the damage or area of concern (phone photos are fine)
  • Your insurance carrier name and claim number (if applicable)
  • Best time and number to reach you
  • A rough idea of when the damage occurred or project timeline
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Prolific Design-Build & Restoration — Federal Way, WA

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