HVAC Permit in King County, Washington

Permit required?

Yes, a permit is required.

When a permit is usually needed

For installation or replacement of furnaces, air conditioners, heat pumps, fireplaces, or wood stoves in unincorporated King County

Permit cost and what affects it

Fees are set by the locality and are not published here. See the official fee schedule or contact the office for current amounts.

Permit costs generally depend on the project valuation, the scope of work, and the inspections required. Ask the office how the fee is calculated for your specific project.

Where to apply

• Official permit page
• Permit portal

Frequently asked questions

Do you need a hvac permit in King County?

A mechanical permit is required in unincorporated King County for installation or replacement of HVAC equipment including furnaces, air conditioners, heat pumps, fireplaces, and wood-burning stoves. Mechanical permits are issued by the King County Permitting Division and applied for through MyBuildingPermit.com. These rules apply to unincorporated King County only. Always confirm with the King County Department of Local Services Permitting Division before starting.

How much does a hvac permit cost in King County?

Fees are set by King County and are not published here. Contact the office for current amounts.

How long does a hvac permit take in King County?

Processing time for a hvac permit in King County varies by workload and project scope. Contact the King County Department of Local Services Permitting Division for a current estimate.

Where do you apply for a hvac permit in King County?

You can apply through the King County permit portal or contact the King County Department of Local Services Permitting Division directly. The links are listed on this page.

Official sources

• https://kingcounty.gov/en/dept/local-services/certificates-permits-licenses/permits/permits-inspections-codes-buildings-land-use/do-you-need-a-permit
• https://kingcounty.gov/en/dept/local-services/certificates-permits-licenses/permits