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A commercial building permit is required in unincorporated King County to construct a new commercial building or for certain tenant improvements to assure the development is consistent with building codes and other applicable regulations. See legal authority Title 16 & 20 of the King County Code

Get an estimate:

What activities require this permit?

  • a new commercial building structure
  • tenant improvements to finish or remodel existing building shell
  • mechanical (HVAC) or fire systems
  • changes in occupancies
  • installation of new, or changes to existing signs & cellular antennas
  • a commercial building permit will require related permits
  • commercial building permits often require SEPA

How do I get an application?

How do I submit my application?

  • Refer to pre-applications as a commercial building permit often requires a pre-application meeting prior to application submittal
  • Refer to our bulletin 53, Project Management for Building Permits, for information about projects that require a Project Manager.