Adding less than 3,000 square feet or a deck to an existing single family residence.
Examples of work covered by this (BR) permit include:
- Adding on to an existing house (new or replaced living space)
- Adding an attached garage or carport
- Adding detached buildings and structures, like garages, storage and equipment sheds, retaining walls greater than four feet in height
- Building a deck or deck with spa
- Repairing, expanding or constructing a dock, boat house, boat lift or bulkhead greater than four feet in height
- Constructing a swimming pool, bathing or hot tub (24 or more inches in depth and all in-ground)
This permit also includes:
- Clearing and grading
- Demolition work, if required
- Electrical (except temporary power)
- Mechanical (except fire protection)
Note: Additions greater than 3,000 gross square feet of new and/or replaced floor area require a single-family combo permit (BS).
Apply for this permit online at MyBuildingPermit. When entering your Application Information, choose the following:
- Application type: Building
- Project type: Single Family Residential
- Activity type: Structure Addition
- Scope of work: Accessory Building or Deck or Porch or Residence
The documents listed below are the minimum necessary to proceed with the application process. If you believe that a required submittal document does not apply to your project, please upload the Document Waiver Form in place of the required document.
- Architectural Plan
- Boundary and Topographic Survey
- Construction Stormwater Pollution Prevention Plan (CSWPPP)
- for projects with less than 7,000 square feet of clearing and less than 100 yards of grading, a CSWPPP Short Form for Small Construction Projects may be submitted.
- Energy Code Sheet or Envelope Summary (Residential Energy Code Worksheet)
- Residential Site Plan
- Storm Drainage Report
- Stormwater Site Plan
- Structural and Lateral Calculations
- Structural Plan
- Value of Improvements Form
For assistance with electronic plan submittals, refer to Requirements for Electronic Plans
These items may be required during plan review, as determined by the scope of your project.
- Adult Family Home Requirements
- Critical Areas or Shoreline Land Use Permit
- Geotechnical Report
- King County Health Department Approval
- required for installation of septic tanks or if the dwelling is served by a septic system, and if there is a private well on the property. During review, submit your approval in the form of a letter or stamped plan from the King County Health Department.
- Pool/Spa Plan
- Title Report