Patio Permit in King County, Washington
By Mario Bailey Last checked 2026-07-06 · 1 official source
Verified against official sources From an official sourceIt depends
Quick answer
King County does not require a permit for uncovered decks and platforms 30 inches or less above the ground, which covers typical at-grade patios. A building permit is required for covered patios or elevated structures, and critical-areas review can apply near streams, wetlands, or steep slopes.
Typical threshold: at-grade patios and uncovered decks 30 inches or less above ground are exempt; covered patios and taller structures require a building permit.
Who is pulling this permit?
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- Who pulls the permit, you or me, and is the permit fee included in the bid?
- Which inspections will this job need, and who meets the inspector on site?
- Is your contractor license active in this locality, and under which business name?
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When a permit is usually needed
For patio covers or any deck or platform more than 30 inches above ground
What your patio permit must meet in Washington
Washington's 2021 Residential Code (WAC 51-51, effective statewide March 15, 2024) carries no mandatory statewide construction standard for patio covers: the model code's patio-cover appendix applies only where a city or county specifically adopts it, so patio-cover build requirements are set locally.
- Appendices to the Washington State Residential Code, including the model code's patio-cover appendix, are not part of the statewide default: an appendix applies only if a local jurisdiction's adopting ordinance specifically references it and the state building code council has approved that adoption (WAC 51-51-0102).
- Where a patio cover adjoins a habitable room and is used to satisfy that room's natural-light requirement, state code requires an openable area between the room and the patio cover of not less than one-tenth of the interior room's floor area, with a 20 square foot minimum (WAC 51-51-0303, R303).
Based on 2021 Washington State Residential Code (WAC 51-51), based on the 2021 IRC. Read the code. Local amendments can be stricter; confirm the current requirement with your office before you build.
What patio permit costs in King County
No separate patio line; the deck and accessory building category (which the county states includes porches or decks of any size) applies, $772 minimum application review plus $2.46 per sq ft inspection plus the $6.50 state building code surcharge, per the 2026 single family residential fee guide.
How King County compares in Washington
| Jurisdiction | Permit needed? | Threshold |
|---|---|---|
| Bellevue | No permit needed | Not specified |
| Clark County | It depends | Patio and concrete slabs on the ground grade are exempt from permit but may not be built on easements; adding a patio cover or enclosing a covered patio requires a building permit under the ADS permit type. |
| King Countythis page | It depends | at-grade patios and uncovered decks 30 inches or less above ground are exempt; covered patios and taller structures require a building permit |
| Pierce County | It depends | At-grade patios, treated the same as exempt sidewalks and driveways, are exempt if not more than 30 inches above grade at any point and not over any story or basement below; an attached, roofed patio cover requires a building permit regardless of size. |
| Seattle | No permit needed | Not specified |
| Snohomish County | It depends | open at-grade patios are treated as exempt sidewalks and driveways under SCC 30.50.103(1)(e) with no size limit; freestanding patio covers (roofed, not attached to another structure) are exempt only if 200 sq ft or less inside the UGA or 400 sq ft or less outside the UGA; larger or attached patio covers require a permit |
| Tacoma | It depends | at-grade flatwork such as sidewalks and driveways is exempt from a building permit, though separate site-development permits can apply; covered patios require a building permit |
How to apply 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).
- 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:
King County Department of Local Services Permitting Division
- 919 SW Grady Way Suite 300, Renton, WA 98057
- Phone: (206) 296-6600
- Email: PermitQuestions@kingcounty.gov
Inspections and closing out your permit
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.
- 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).
- 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).
- 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).
- 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).
- 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.
Your Patio Permit checklist for King County
- Confirm the requirement. Sometimes, depending on the project. Typical threshold: at-grade patios and uncovered decks 30 inches or less above ground are exempt; covered patios and taller structures require a building permit. Usually needed: For patio covers or any deck or platform more than 30 inches above ground.
- Budget the fee. No separate patio line; the deck and accessory building category (which the county states includes porches or decks of any size) applies, $772 minimum application review plus $2.46 per sq ft inspection plus the $6.50 state building code surcharge, per the 2026 single family residential fee guide. Official fee schedule.
- Apply. 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. Start at the King County permit portal.
- Keep the office details handy. King County Department of Local Services Permitting Division. Phone: (206) 296-6600. Address: 919 SW Grady Way Suite 300, Renton, WA 98057.
- Plan for inspections. 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.
Compiled from the official sources on this page. Last checked 2026-07-06.
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Permitting activity in King County
In 2024, King County authorized permits for 10,564 new residential housing units (2,352 single-family, 8,212 in multi-family buildings), valued at $2.7B, down from10,601 the year before. That works out to about 4.5 permits per 1,000 residents.
Source: U.S. Census Bureau, Building Permits Survey, 2024 annual data · population 2,340,211.
About King County
King County has about 988,330 housing units. The median home is valued at $811,200, against a median household income of $122,148. About 56% of homes are owner-occupied, and the typical home was built around 1983.
Source: U.S. Census Bureau, American Community Survey 2023 5-year.
Frequently asked questions
- Do you need a patio permit in King County?
- King County does not require a permit for uncovered decks and platforms 30 inches or less above the ground, which covers typical at-grade patios. A building permit is required for covered patios or elevated structures, and critical-areas review can apply near streams, wetlands, or steep slopes. At-grade patios and uncovered decks 30 inches or less above ground are exempt; covered patios and taller structures require a building permit. Always confirm with the office before starting.
- How much does a patio permit cost in King County?
- No separate patio line; the deck and accessory building category (which the county states includes porches or decks of any size) applies, $772 minimum application review plus $2.46 per sq ft inspection plus the $6.50 state building code surcharge, per the 2026 single family residential fee guide. See the official fee schedule for current amounts.
- Where do you apply for a patio 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.
From the Library
What else needs a permit in King County
Every other permit type we have verified for this jurisdiction, with the rule that applies here.
| Project | Permit needed? | Threshold | Typical fee |
|---|---|---|---|
| Deck Permit | It depends | uncovered decks 30 inches or less above ground do not require a building permit in unincorporated King County; decks over 30 inches above grade require a permit | Most permit fees increased approximately 14% on January 1 2026 plus a $126 application... |
| Electrical Permit | Permit required | Not specified | Set by state L&I, not King County, under WAC 296-46B-906 (effective 7/1/2026): new sing... |
| Fence Permit | It depends | fences 6 feet or less do not require a building permit in unincorporated King County; fences over 6 feet require a permit | Most permit fees increased approximately 14% on January 1 2026 plus a $126 application... |
| HVAC Permit | Permit required | Not specified | Mechanical installation-only permit is a flat $183 inspection fee covering up to six fu... |
| Plumbing Permit | Permit required | Not specified | Issued by Public Health Seattle and King County rather than the county Permitting Divis... |
| Pool Permit | It depends | prefabricated above-ground pools less than 24 inches deep and not exceeding 5000 gallons are exempt; all other pools require a building permit in unincorporated King County | Most permit fees increased approximately 14% on January 1 2026 plus a $126 application... |
| Roof Replacement Permit | No permit needed | Not specified | Most permit fees increased approximately 14% on January 1 2026 plus a $126 application... |
| Shed Permit | It depends | storage sheds 200 sq ft or less as accessory to a residential house do not require a building permit in unincorporated King County; sheds over 200 sq ft require a permit | Most permit fees increased approximately 14% on January 1 2026 plus a $126 application... |
| Solar Permit | It depends | roof-mounted solar PV panels weighing less than 4 pounds per square foot on residences do not require a building permit; heavier installations require a permit | Most permit fees increased approximately 14% on January 1 2026 plus a $126 application... |
Patio Permit in other Washington localities
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://www.solanocounty.gov/patios-decks
- https://www.escondido.gov/DocumentCenter/View/457/8B---Solid-Roof-Patio-Cover-PDF
- https://app.leg.wa.gov/wac/default.aspx?cite=51-51-0102
Verified by a person against the sources above on 2026-07-06, not confirmed with King County Department of Local Services Permitting Division. Rules change; confirm before you build. How we verify.
Last checked: 2026-07-06Report an error on this page
Compare Patio Permit requirements across Washington localities
Permit office
King County Department of Local Services Permitting Division
(206) 296-6600Permit portalWashington rule changes
- Bellevue, WA sets a flat $290 re-roof permit fee (Ordinance 6879)
Ord. 6879 · 2026-07-25