Permit Requirements for Building a Deck in Washington: What Homeowners Need to Know

Adding a deck to your home can transform your outdoor space—but in King County and Snohomish County, it’s not just about design and materials. It’s about following local building codes and securing the right permits before the first nail is hammered in.

If you’re planning to build a deck in cities like Bellevue, Kirkland, Everett, or Lynnwood, understanding the permit process is essential. Skipping this step could cost you thousands in fines—or even require you to remove your deck completely.

Partnering with a licensed Washington deck contractor ensures your project complies with city and county requirements from day one.

When Do You Need a Permit to Build a Deck?

In King and Snohomish counties, permits are generally required for any of the following:

• Decks attached to your house
  
  
• Decks 30 inches or more above the ground
  
  
• Decks that will support a roof or cover
  
  
• Major modifications to existing decks
  
  

Even some ground-level or freestanding decks may require permits, depending on the city and zoning code. Always check with your local building department to confirm.

Specific Local Rules:

• Bellevue & Kirkland (King County): Require a building permit for any deck over 30 inches high or attached to the home. Electrical permits are needed for lighting or outlets.
  
  
• Everett & Lynnwood (Snohomish County): Also follow IRC standards and require structural plans for load-bearing decks, even if they are low to the ground.
  
  

What You’ll Need for a Deck Permit Application

While exact requirements vary slightly by city, most applications require:

• A site plan showing the location of your deck in relation to your house and property lines
  
  
• Framing and elevation drawings
  
  
• Details on materials, footings, stairs, and railing systems
  
  
• Your contractor’s license number (if hiring professionals)
  
  
• Estimated project costs for fee calculations
  
  

Permit fees typically range from $250 to $650, depending on the project’s size and complexity.

Deck Code Requirements in King & Snohomish Counties

Here are common building codes that apply across both counties:

Cities like Bellevue and Everett also require inspections throughout the project, including:

• Pre-pour footing inspection
  
  
• Mid-project framing inspection
  
  
• Final code-compliance check
  
  

To ensure a smooth process, it's best to hire a professional deck builder serving King and Snohomish County who understands each city’s permit nuances.

What Happens If You Skip the Permit?

Avoiding permits might seem easier, but it can lead to:

• Fines up to $1,000 per day in some cities
  
  
• Forced removal of non-compliant structures
  
  
• Delays in selling your home
  
  
• Issues with homeowners insurance coverage
  
  

City inspectors can issue stop work orders if they discover an unpermitted project—even mid-construction. It’s just not worth the risk.

Final Thoughts: Plan Smart, Build Safe

Whether you’re creating a cozy backyard retreat in Lynnwood or an elevated entertaining space in Kirkland, understanding permit requirements is essential. In King and Snohomish counties, building without the right approvals can lead to expensive setbacks.

Make sure your deck is designed to code, structurally sound, and fully permitted before breaking ground. Need help navigating the process? The experts at Legacy Decking offer full-service deck design and construction that meets every regulation in King and Snohomish counties.

We take care of everything—from drawings and permits to inspections and final touches. Our team will also walk you through every option for materials, layout, and custom upgrades so your new deck is both safe and stunning.