Seattle, Washington Plumbing Local Permit Ordinances and Codes
Seattle Municipal Plumbing Permit Ordinances
In Seattle, Washington, the primary authority responsible for enforcing plumbing permit ordinances is Public Health - Seattle & King County. While the Seattle Department of Construction and Inspections (SDCI) handles various building permits, plumbing and gas piping permits, along with their inspections, fall under the jurisdiction of Public Health - Seattle & King County.
The Seattle Plumbing Code is based on the Uniform Plumbing Code (UPC) with local amendments. The current code in effect is the 2021 Washington State Plumbing Code with Seattle amendments.
Specific Local Zoning or Fee Nuances for Seattle:
- Permit Fees: Plumbing and gas piping permit fees are administered by King County Public Health and are funded through a full cost recovery mandate. This means that the revenue generated from these fees must cover the program's operational costs.
- Fee Structure Changes (Effective January 1, 2025): The permit fee structure is being revised and simplified. It will consist of an initial base fee of $132, plus a per-fixture fee of $26. Previously, fees were based on the number of fixtures and differed for gas versus plumbing permits.
- Reinspection Fees: A reinspection fee of $40 may be assessed for each inspection or reinspection if the work is incomplete or corrections are not made.
- Double Fees: If work requiring a permit is commenced without first obtaining one, double the standard fee may be charged, unless it's proven that the work was urgently necessary and obtaining a permit beforehand was not practical.
- Plan Review Fees: For projects requiring plan review, separate fees are assessed. For plumbing permits, this fee is typically 50% of the building permit fee, based on the portion of the total valuation related to plumbing.
- Water Conservation Requirements: Recent updates to the Seattle plumbing code (approved in 2023) focus on water conservation. These include requirements for low-flow fixtures in new construction and expanded options for greywater systems. Specific fixture flow rates are mandated, such as 1.28 gallons per flush for toilets and 2.5 gallons per minute for showerheads.
- Re-pipe Project Fees: Fees for commercial re-pipe projects are calculated based on the hourly operating rate multiplied by the anticipated number of inspections.
Resources to Learn More
Because Seattle is located within King County, the following broader county regulations may also apply to your project:
Washington, King County Plumbing Permit Regulations and County Ordinances for Unincorporated Areas
King County Plumbing Permit Requirements
In King County, Washington, plumbing and gas piping installations, relocations, or alterations require a permit. Public Health - Seattle & King County has jurisdiction over permits for Seattle and unincorporated areas of King County. If your property is located within another incorporated city in King County, you will need to obtain permits from that city's building department. You can verify jurisdiction using the King County Parcel Viewer.
Unincorporated Areas
For properties in unincorporated King County, the Department of Local Services, Permitting Division, is responsible for issuing land use, building, and fire regulatory permits. Plumbing and gas piping permits for these areas are handled by Public Health - Seattle & King County.
Permit Application Process
Permits can generally be applied for online through the Public Health Permit Center or the King County Permitting Portal. Some applications may require submission via email or in person.
When applying for a plumbing permit, you will need to provide information such as the project location, property owner details, parcel number, building use, and occupancy type. If a professional plumber is hired, they must be a licensed contractor. Homeowners may be able to perform their own plumbing work on their residence, but must adhere to specific instructions.
Certain projects, particularly those involving specific occupancies or complex systems, may require a plumbing plan review. The plans can be submitted by anyone, but the permit will only be issued to the licensed plumbing contractor.
Effective March 15, 2024, projects in unincorporated King County are required to be designed using the 2021 Washington State construction codes, unless the building permit was vested in a previous code cycle.
Resources to Learn More
The following statewide building codes and regulations apply universally to all jurisdictions within Washington:
Washington Plumbing Legislation, Codes, and Guidelines
Plumbing Codes and Legislation in Washington State
The state of Washington regulates plumbing systems through the adoption of the 2021 Uniform Plumbing Code (UPC), which is published by the International Association of Plumbing and Mechanical Officials (IAPMO). This model code is adopted by reference and modified by state-specific amendments to create the Washington State Plumbing Code, codified under Chapter 51-56 of the Washington Administrative Code (WAC). These regulations are established under the authority of the Revised Code of Washington (RCW) Chapter 19.27, which governs the State Building Code.
Primary State Agencies
Two primary state entities oversee the plumbing regulatory framework in Washington:
- Washington State Building Code Council (SBCC): This council is responsible for the adoption, maintenance, and amendment of the state building codes, including the Washington State Plumbing Code. They regularly review and update these codes to ensure they remain consistent with state safety and health standards.
- Washington State Department of Labor & Industries (L&I): This department is the primary authority for the administration of plumber certification, plumbing contractor licensing, and enforcement of professional standards. While the SBCC sets the technical code, L&I manages the workforce and business regulations associated with the plumbing trade, as outlined in RCW Chapter 18.106 and WAC Chapter 296-400A.
It is important to note that while the state sets the minimum standards, local jurisdictions (cities and counties) are responsible for issuing permits and conducting inspections. Local authorities may also adopt additional, stricter amendments to the state code.
Resources to Learn More