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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Prolific Design-Build and Restoration logo - insurance restoration contractor King County WA
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Hail Damage Roof Repair King County

⚠️ Recent Hail Storm in King County?

Free hail damage roof inspection — we work directly with your insurance company.

Hail Damage Roof Repair & Insurance Claims in King County, WA

If your King County home was hit by hail, your roof may have damage you can’t see from the ground. Hail dents shingles, cracks tiles, and compromises the protective granule layer — leading to leaks, mold, and thousands in water damage if not repaired quickly.

Prolific Design-Build and Restoration specializes in hail damage roof repair and insurance restoration. We handle the entire process: free inspection, detailed damage documentation, insurance claim filing, adjuster coordination, and professional repair or replacement — all at no out-of-pocket cost when covered by insurance.

Signs of Hail Damage on Your Roof

  • Dented or bruised shingles — soft spots where granules have been knocked loose
  • Cracked or split shingles — visible fractures from hail impact
  • Missing granules — dark spots or exposed asphalt on shingle surface
  • Dented gutters, vents, or flashing — metal components show hail impact clearly
  • Damaged siding or window screens — hail rarely hits just the roof

Our Hail Damage Repair Process

  1. Free Roof Inspection — We climb on your roof and document every impact point with photos and measurements.
  2. Insurance Claim Filing — We help you file the claim with detailed documentation that adjusters need.
  3. Adjuster Meeting — We meet your insurance adjuster on-site to walk through the damage together.
  4. Xactimate Estimate — Our estimates use the same software your insurance company uses, so approvals are faster.
  5. Professional Repair — Licensed crew completes the repair using manufacturer-spec materials.
  6. Final Inspection — Walkthrough with you to ensure everything meets our standards.

Insurance Carriers We Work With

State Farm, Allstate, PEMCO, USAA, Farmers, Liberty Mutual, Safeco, Nationwide, American Family, Hartford, Travelers, Erie — and every other carrier operating in Washington State.

Why King County Homeowners Choose Prolific Design-Build and Restoration

  • $0 out-of-pocket on approved insurance claims (minus your deductible)
  • 24/7 emergency response for active leaks and severe damage
  • Licensed & insured — WA Contractor License PROLISN788QN
  • Xactimate certified — estimates match your insurance company’s format
  • Complete documentation — photos, moisture readings, material specs for every job

Get Your Free Hail Damage Inspection Today

Don’t wait — most insurance policies have a time limit for filing hail damage claims.

📞 Call (253) 444-8822

Service Areas: Seattle, Bellevue, Kent, Renton, Federal Way, Auburn, Tacoma, Burien, Tukwila, SeaTac, Maple Valley, Covington, Sammamish, Issaquah, Mercer Island, and all of King County, WA.

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

📋 Get a Free Estimate