Free Permits When We Build Your ADU
Most builders hand you a permit bill on top of construction costs. We don't. When you build with Seattle ADU Builders, your entire permit package — site plans, land use permits, building permits, engineering — is absorbed into your construction contract at no additional charge.
Free
Feasibility Study
Free
Permit Package
Perfect
Build
How Our Permit Package Works
ADU permitting in King County involves navigating state mandates (HB 1337), city-specific ordinances, county regulations, and environmental overlays. Most homeowners underestimate the time and expertise required to get permits approved on the first submission.
Our permit package covers everything: professional site plans, land use permits (required for unincorporated county properties — not needed within city limits), and building permits with tiered pricing based on project complexity. The total typically runs less than 1% of your project cost, plus $1,000–$2,000 in government filing fees.
Need permits without a build contract? We offer the permit package as a standalone service — see our pricing structure below. But most clients choose the full build path where permits are included at no charge.
City vs. County: What Permits Do You Need?
Within City Limits
Seattle, Bellevue, Redmond, Kirkland, Renton
- Site plan
- Building permit
- Land use permit not required
Faster & simpler process
Unincorporated County
Rural King County, UGA areas
- Site plan
- Land use permit (county requirement)
- Building permit
Additional land use step required
Not sure which jurisdiction you're in? Our free feasibility study determines this automatically.
Standalone Permit Pricing
For homeowners who need permits without a build contract. All fees are waived when you build with us.
Site Plan
| Component | Pricing | Details |
|---|---|---|
| Base Site Plan | Flat rate | Standard residential lot under 0.5 acres |
| Large Lot Surcharge | Per-acre cost | Properties over 0.5 acres |
| Site Plan Drafting | 10% to surveyor | Professional site plan by our licensed team |
Building Permits (Tiered by Complexity)
Standard
Garage conversion, basement ADU, simple attached
Straightforward projects with minimal structural changes
Moderate
Attached addition, above-garage unit
Projects requiring moderate engineering and design coordination
Complex
Custom detached DADU, multi-story, challenging site
Full custom design with structural engineering, site challenges, or CUP process
Total Standalone Permit Package
Less than 1% of total project cost + $1,000–$2,000 government fees
Typical total
$4,000–$6,000
Build with us? Permits are on the house.
When you sign the Letter of Intent and build with Seattle ADU Builders, the entire permit package cost is absorbed into your construction contract. You pay nothing extra for permitting.
What's Included
- Full zoning verification for your specific parcel
- Setback and lot coverage analysis
- Utility connection assessment (sewer, water, electrical)
- Critical areas review (wetlands, flood zones, steep slopes)
- Shoreline Management Act areas check
- Professional site plan by licensed surveyor
- Land use permit application and management (county properties)
- Building permit drawings and structural engineering
- Building permit submission and follow-through
- Ongoing communication with planning staff through approval
- Pre-application meeting with planning department (if needed)
Learn More About ADU Permitting
Read our detailed permit guides: Seattle permit process, King County permits, permit cost breakdown, and realistic timelines.
Ready to build? Explore our detached ADU and attached ADU construction services.
Frequently Asked Questions
What does the Full Permit Package include?
The package covers your complete permitting process: site plan preparation, zoning verification, setback analysis, utility assessment, critical areas review, SMA jurisdiction check, King County DPER permit application (for unincorporated properties), building permit drawings, engineering, and submission management. When you build with us, the entire permit cost is included in your construction contract — you pay nothing extra.
Do I need a land use permit?
Only if your property is in unincorporated King County. Properties within Seattle city limits go straight to DCI building permits — no separate land use permit required. Our feasibility study determines your jurisdiction automatically.
How much does permitting cost as a standalone service?
Our permit package typically totals less than 1% of your project cost, plus $20,000–$50,000 in Seattle permit, impact, and utility connection fees. However, when you build with us, the entire permit package is included at no additional charge — it's absorbed into your construction contract.
What type of permit does my ADU need?
Most ADUs in Seattle require a standard building permit through Seattle DCI. DADUs are governed by SMC 23.44.041 and AADUs by SMC 23.44.025. Projects in Shoreline Management Act (SMA) areas require additional SMA review. Unincorporated King County properties go through King County DPER instead of Seattle DCI.
How long does the ADU permitting process take?
Seattle DCI: 6–10 weeks for standard DADU permits; King County DPER: 8–14 weeks. SMA areas add 4–8 weeks. These assume a complete initial submission — which is why having a specialist matters.
What if my property doesn't qualify for an ADU?
If our analysis determines your property doesn't qualify, we'll tell you honestly. We'd rather give you a straight answer than waste your time and money.
Do I need a permit for a garage conversion?
Yes. Converting a garage to a dwelling unit requires a change-of-use permit plus building permits for the conversion work (plumbing, electrical, insulation, egress windows). The good news: existing structure conversions are allowed even if the structure doesn't meet current setback or lot coverage standards under HB 1337 and Seattle's code.
