Patio Permit in King County, Washington

How to apply in King County

In King County, applying for a patio permit means submitting a site plan and framing plans for a roofed patio cover, since a cover is treated as its own permitted structure regardless of size. A plain concrete or paver patio slab at or near grade is, by contrast, often exempt from that same building permit requirement.

What most patio permit applications include:

• Filing a permit application with the local building department, which only the property owner or an authorized agent may sign, since a patio cover is treated as its own permitted structure regardless of size (IRC R105.1).
• For King County, a scaled site plan showing the new patio cover's size and location relative to the house and other existing structures, with dimensioned distances to all property lines so required setbacks can be verified before the permit is approved (IRC R106.2).
• Construction documents such as a framing plan and elevation, showing rafter or beam sizes and spacing, the distance between supporting posts, and the method of attachment to the house, drawn with enough clarity for the building official to confirm the work will conform to the code (IRC R106.1).
• For the roof structure itself, plans showing compliance with the patio cover appendix's structural limits, such as adequate footing sizes for the applied post loads, since a shallow slab on grade may substitute for a deeper footing only in limited cases up to about 750 pounds of load per post (IRC Appendix AH, Section AH105.2).
• By contrast, an at grade concrete or paver patio that is not attached to the dwelling and stays within the code's small flatwork thresholds, similar to a sidewalk, driveway, or low deck under 200 square feet and 30 inches high, commonly needs no building permit at all, so none of the plan review steps above apply (IRC R105.2).

General submittal guidance from 2021 International Residential Code (IRC), Sections R105 and R106, with Appendix AH Patio Covers (named Appendix H in the 2012, 2015, and 2018 editions). Source. King County Department of Local Services Permitting Division sets the exact checklist for King County.

Where to apply in King County:

• Official permit page
• Online permit portal (apply, upload plans, check status)

Inspections and closing out your permit

In King County, a permitted patio cover follows the same footing, frame, and final inspection sequence used for any small accessory structure, since the posts and roof framing have to be checked before they are covered and again once the work is done. An at grade patio slab that qualifies as exempt flatwork usually needs no building inspection at all, because inspections only attach to work that required a permit in the first place.

1. In King County: a footing inspection once the excavation, forms, and any reinforcing steel are in place but before concrete is poured, confirming the posts supporting a patio cover will bear on adequate footings (IRC R109.1.1).
2. In King County: a frame inspection after the rafters, beams, posts, and any required rough in work are in place but before the roof sheathing or covering material conceals them, since a solid patio cover roof cannot be signed off once it is covered without this check (IRC R109.1.4).
3. In King County: a final inspection once all permitted work, including roofing and post anchorage, is complete, which the code requires before the structure may be used (IRC R109.1.6).
4. In King County: an at grade concrete or paver patio that qualifies as exempt flatwork under the permit rules is not subject to any of these inspection stages, since the inspection sequence only attaches to work that required a permit in the first place (IRC R105.2).
5. In King County: each inspection has to be requested by the permit holder rather than happening automatically, and the approved plans and permit card need to be on site and available when the inspector arrives (IRC R109.3).

Schedule each inspection in advance and pass the final before you use the work or close the permit. Request inspections through the King County permit portal or by phone at (206) 296-6600.

Inspection sequence from 2021 International Residential Code (IRC), Section R109 (Inspections). Source. An open permit left un-inspected can surface later in a title search or home sale.