How to Get a ADU Permit in Yakima County, WA (2026 Guide)
Everything you need to know about adu permits in Yakima County, WA, local requirements, fees, timelines, and how to apply.
By Joey, Founder · Last updated May 15, 2026 · How we research →
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Free Permit Lookup →Do You Need a ADU Permit in Yakima County?
Based on Yakima County's local building codes, you'll need a permit when:
WA, a detached accessory dwelling unit (ADU) requires building, plumbing, electrical, and mechanical permits. Confirm ADUs are allowed in the county zoning code (YCC Title 15A) before applying. Septic capacity must be reviewed by Yakima Health District at (509) 575-4040 if the property is on septic.
WA, an attached ADU (in-law suite, garage conversion with kitchen) requires building, plumbing, and electrical permits. Septic capacity must be reviewed by Yakima Health District at (509) 575-4040 if on septic.
Permit Fees in Yakima County
Contact Yakima County Building and Fire Safety Division for current permit fee information. Fees are typically calculated based on estimated project value.
Here are typical fee ranges for adu projects nationally:
| Project Scope | Typical Permit Fee |
|---|---|
| Garage or basement conversion ADU | $500 – $3,000 |
| Attached ADU (addition) | $800 – $5,000 |
| Detached ADU (new construction) | $1,000 – $8,000+ |
| Impact fees (where applicable) | $0 – $10,000+ (waived in many states) |
| Utility connection fees | $1,000 – $5,000+ (for new water/sewer connections) |
| Architectural plans | $2,000 – $10,000 (separate from permit) |
How Long Does It Take?
In Yakima County, typical approval time for adu permits is about 4 weeks.
More complex projects requiring structural review or variances may take longer. Simple projects may qualify for expedited or over-the-counter review in some cases.
How to Apply for a ADU Permit in Yakima County
- 1 Check requirements: Use our free lookup tool or contact Yakima County Building and Fire Safety Division to confirm your project needs a permit.
- 2 Gather documents: Prepare your application, site plan, construction drawings, and any other required documents.
- 3 Submit online: Yakima County accepts applications online at Yakima County Building and Fire Safety Division.
- 4 Pay fees: Pay the applicable permit fees (Contact for pricing).
- 5 Wait for approval: Your application will be reviewed by Yakima County plan reviewers. Typical turnaround is about 4 weeks.
- 6 Begin work: Once approved, post your permit visibly at the job site before starting work.
- 7 Schedule inspections: Call Yakima County Building and Fire Safety Division at (509) 574-2300 to schedule required inspections at each phase of the project.
Yakima County Building Department Contact
Required Inspections in Yakima County
Most adu projects in Yakima County require inspections at each construction stage:
Foundation Inspection, Footing dimensions, depth below frost line, rebar placement, anchor bolt locations, soil bearing conditions, and compliance with structural engineering plans.
Framing Inspection, Wall framing, headers, connections to existing structure (for attached/conversions), fire separation between ADU and main house, egress windows/doors, ceiling height compliance, and overall structural integrity per approved plans.
Rough-In Trade Inspections, Electrical: circuits, GFCI/AFCI, panel capacity. Plumbing: DWV routing, supply lines, water heater, fixture connections. Mechanical: HVAC ductwork, ventilation, combustion air. All work must be visible.
Final Inspection, All fixtures operational, smoke and CO detectors, GFCI tested, kitchen appliances connected, egress windows functional, address numbers posted, and overall compliance with approved plans. Certificate of occupancy issued upon passing.
Schedule inspections with Yakima County Building and Fire Safety Division at (509) 574-2300 at least 24–48 hours in advance.
Frequently Asked Questions
Whether you need a permit depends on the size and scope of your adu project. In Yakima County, some smaller projects are exempt while larger ones require a permit. Use our free lookup tool to check your specific situation.
Permit fees for adu projects in Yakima County typically range from Contact for pricing. Fees are usually based on the estimated project value.
Typical approval time in Yakima County is about 4 weeks. Complex projects requiring structural review may take longer.
In most cases, homeowners in Yakima County can pull permits and perform work on their own primary residence as an owner-builder. You're still responsible for meeting all code requirements and passing inspections.
Working without a required permit in Yakima County can result in fines, stop-work orders, required removal of completed work, and complications when selling your home.
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Free Permit Lookup →Other Permit Guides for Yakima County, WA
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See Detailed ADU Rules for Yakima County
View all local rules, exemptions, and fee details on the permit page.
ADU Permit Rules →