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Plumbing and gas piping

Find information about plumbing and gas piping permits, installations, inspections, and hiring registered contractors.

Hire a registered contractor

Find guidance on hiring a registered contractor for plumbing and gas piping installations.

Inspections for plumbing and gas piping installations

Learn how to submit a request for an inspection, find an inspector, and view your results.


Find resources and tips on installing water heaters, gas piping, waste and vent pipe installation, and more.

Applications and permits

Learn how to submit a plumbing or gas piping plan review application or get a homeowner's permit.


No in-person counter services

The Environmental Health Services Division no longer offers in-person counter services*. This applies to both our downtown Seattle (Chinook Building) and Bellevue (Eastgate Public Health Center) locations.

Most of our permits can be applied for and renewed online by visiting our online services portal.

*We offer in-person food worker card classes at Chinook and Certified Booth Operator classes at both locations.

Important notifications

Plumbing, gas piping, and backflow device permits shall be obtained for each townhome

Effective March 22, 2021: A plumbing permit, gas piping permit, and backflow device permit shall be obtained for each townhome (single family home) that is constructed under 1 building (roof).

Download the related memorandum for details (35 KB).

Guidance for legionella and building water system closures

To prevent Legionella growth, these systems must be actively managed and maintained. See information and guidance to reduce Legionella growth and other pathogen and corrosion concerns that occur when there is a large drop in building water use.

Based on the current volume of plumbing plan submittals, first review comments are at approximately 10 to 12 weeks. The allowance to request "Expedited Plan Review" is no longer in effect.