How to Get a Plumbing Work Permit in Seattle, WA (2026 Guide)

Everything you need to know about plumbing work permits in Seattle, WA, local requirements, fees, timelines, and how to apply.

By Joey, Founder · Last updated May 15, 2026 · How we research →

$60 – $480 Permit Fees
about 2 weeks Approval Time
4 Local Rules

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Do You Need a Plumbing Work Permit in Seattle?

Based on Seattle's local building codes, you'll need a permit when:

Required·Rule 1

Adding a fixture requires a permit in Seattle, WA.

SourceSeattle Building Code / SDCI
Required·Rule 2

Rerouting plumbing requires a permit in Seattle, WA.

SourceSeattle Building Code / SDCI
Required·Rule 3

Water heater replacement requires a permit in Seattle, WA.

SourceSeattle Building Code / SDCI

These plumbing work projects are typically exempt in Seattle:

Exempt·Rule 1

Replacing a fixture in-kind does not require a permit in Seattle, WA.

SourceSeattle Building Code / SDCI

Permit Fees in Seattle

Based on local Seattle permit data, fees for plumbing work projects typically range:

$60 – $480 Seattle Permit Fee Range

Here's how fees break down by project scope nationally:

Project ScopeTypical Permit Fee
Water heater replacement$50 – $200
Single fixture addition or relocation$75 – $300
Adding a bathroom$150 – $500
Gas line installation$75 – $300
Whole-house repipe$200 – $500+
Sewer line repair/replacement$150 – $500+

Fees are typically calculated based on estimated project value. Contact Seattle Department of Construction & Inspections (SDCI) for exact amounts.

How Long Does It Take?

In Seattle, typical approval time for plumbing work permits is about 2 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 Plumbing Work Permit in Seattle

  1. 1 Check requirements: Use our free lookup tool or contact Seattle Department of Construction & Inspections (SDCI) to confirm your project needs a permit.
  2. 2 Gather documents: Prepare your application, site plan, construction drawings, and any other required documents.
  3. 3 Submit online: Seattle accepts applications online at Seattle Department of Construction & Inspections (SDCI).
  4. 4 Pay fees: Pay the applicable permit fees ($60 – $480).
  5. 5 Wait for approval: Your application will be reviewed by Seattle plan reviewers. Typical turnaround is about 2 weeks.
  6. 6 Begin work: Once approved, post your permit visibly at the job site before starting work.
  7. 7 Schedule inspections: Call Seattle Department of Construction & Inspections (SDCI) at (206) 684-8600 to schedule required inspections at each phase of the project.

Seattle Building Department Contact

NameSeattle Department of Construction & Inspections (SDCI)
Apply OnlineApply online
Address700 5th Ave., Suite 2000, Seattle, WA 98104
HoursMon/Wed/Fri 9am-3pm, Tue/Thu 10:30am-3pm

Required Inspections in Seattle

Most plumbing work projects in Seattle require inspections at each construction stage:

Inspection·Stage 1

Rough-In Plumbing Inspection, Pipe sizes and materials correct, drain slope (1/4 inch per foot for pipes under 3 inches), vent routing and distances per IRC Table P3105.1, cleanout placement, pipe support and hangers, firestopping at penetrations. Supply lines pressure-tested at 50 PSI minimum for 15 minutes. DWV system water-tested (filled to 10 feet above highest fitting, held 15 minutes). Gas piping tested at 3 PSI for 10 minutes.

WhenAfter all DWV and supply piping is installed but before walls, ceilings, or floors are closed, inspector must see all piping
Common FailuresIncorrect drain slope, vent too far from trap, missing cleanouts, pipes not properly supported, pressure test failures (leaks), S-traps instead of P-traps.
Inspection·Stage 2

Shower Pan / Liner Test (if applicable), Pan filled with water to the threshold height, held for 15 minutes minimum with no leaking. Liner properly installed and turned up walls. Drain connection sealed.

WhenAfter the shower pan liner or waterproof membrane is installed but before tile
Common FailuresLeaking at drain connection, liner punctures, liner not extending high enough on walls.
Inspection·Stage 3

Final Plumbing Inspection, Every fixture drains properly, all traps filled with water, no leaks at any connections, gas connections leak-tested (if applicable), water heater installation complete and correct (T&P valve, expansion tank, venting, strapping), backflow prevention devices in place, and hose bibb vacuum breakers on all exterior faucets.

WhenAfter all fixtures are installed, connected, and operational
Common FailuresLeaks at fixture connections, water heater T&P discharge pipe missing or improperly terminated, missing expansion tank, gas leak at appliance connection, missing backflow prevention on exterior hose bibbs.

Schedule inspections with Seattle Department of Construction & Inspections (SDCI) at (206) 684-8600 at least 24–48 hours in advance.

Frequently Asked Questions

Whether you need a permit depends on the size and scope of your plumbing work project. In Seattle, some smaller projects are exempt while larger ones require a permit. Use our free lookup tool to check your specific situation.

Permit fees for plumbing work projects in Seattle typically range from $60 – $480. Fees are usually based on the estimated project value.

Typical approval time in Seattle is about 2 weeks. Complex projects requiring structural review may take longer.

In most cases, homeowners in Seattle 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 Seattle can result in fines, stop-work orders, required removal of completed work, and complications when selling your home.

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Plumbing Work Permits in Nearby Cities

See plumbing work permit requirements in other Washington cities:

See Detailed Plumbing Work Rules for Seattle

View all local rules, exemptions, and fee details on the permit page.

Plumbing Work Permit Rules →
Disclaimer: This guide provides general information about plumbing work permit requirements in Seattle, WA. Requirements can change. Always confirm with Seattle Department of Construction & Inspections (SDCI) before starting any project. PermitMint provides general guidance, not legal advice.