Decks
Permit Required:
Before making any repairs, additions or modifications to a deck that is more than 30 inches above grade (measured to the lowest point within six feet of the deck), you need a permit. Note: Removing, altering or repairing railings or guards is considered a modification.

Exemptions:
If you are only replacing / repairing non-structural decking boards, you are exempt.

Important Note:
Be aware that even if no permit is required, any modified decks or patios must still meet current land use regulations. These include, but are not limited to, the maximum impervious surfaces allowed on your lot. Please contact the Permit Center if you are not sure.

Single Family Deck Permit Submittal Requirements:

• General Permit Application Form
• Two sets of plans (see below for plan requirements)
• Affidavit of Agent Authority or Affidavit of Ownership

Site plans must include (required if the size of the deck is changing):

• Front, rear and side yard setbacks
• Property area
• All structure dimensions / sizes (for impervious surface calculations)
• Impervious surface calculations
• Title block - include property owner information, site address and page number

Deck plans must include:

• Fully dimensioned floor plan, ¼”/ft. scale
• Framing plan and details (fully-dimensioned framing plan showing spacing and span of posts, handrails and size of pier footings)
• Stair details
• Handrail details
• Guardrail details
• Foundation details

Tipsheets:
You may include the MyBuildingPermit.com tipsheets instead of creating your own:

• Basic Deck Tipsheet
• Guards / Handrails Tipsheet
• Basic Stairs Tipsheet

Fences
Maximum Height (Residential)

• The maximum height in the front setback is four feet.
• The maximum height in the side and rear setbacks are six feet.
• Additional HOA restrictions or approvals may be required.
• See IMC 18.07.120 for further information.

Residential fences do not require a permit unless the deck is in a critical area, is over six feet in height or has other land use restrictions.

Determining your property line
In newer-platted areas you may find buried corner markers - look for a piece of rebar in the ground. The Permit Center or King County may have plat maps to assist you in finding your property lines and/or dimensions. Please be aware that ultimately it is up to the property owner to verify property line locations, which may require a professional survey.