Once you decide to build a deck, you’ll likely want to get started as soon as possible. However, before beginning your deck installation, you’ll want to ensure that you have the proper permits for your city and state and are familiar with the parameters your deck construction experts must meet.

In Washington and Idaho, most decks require a permit. Getting a permit isn’t as simple as asking if you can build a deck and being approved or denied. You will have to show a site plan and a building plan showing the details of how your deck will be built.

This process will require you to draw an outline of your deck’s various elements and label all its components. You will need to provide the following information along with your application for a deck permit:

  • Dimensions of the completed deck and individual components of the deck
  • Type of lumber used (and whether it is pressure-treated)
  • Size of lumber used
  • Type of connectors used
  • Type of fasteners used
  • Footing location, size, and depth
  • Height of walking surface
  • Height of guardrail
  • Height of entry/exits 

Idaho Permit Requirements

In Post Falls, Idaho (Kootenai County), a building permit must be acquired before deck construction if the deck exceeds 200 sq ft in area, is attached to any structure, serves as the main exit or entry of a building, or if it is higher than 30 inches above the ground. However, some counties in Idaho require a building permit when a deck is built over 12 inches above grade. Since these parameters can vary by location, you’ll always want to double-check with your local building department.

Keep in Mind

In most Idaho counties, pressure-treated wood is required for all deck ledgers. The screws, washers, bolts, nails, and nuts used with preservative-treated wood must be hot-dipped, zinc-coated, galvanized steel, silicon bronze, or copper. In addition, all connectors used to build the deck must be stainless or galvanized steel.

Washington Permit Requirements

In Washington, you will need a permit to build your deck if it exceeds 200 sq ft in area or is over 30 inches off the ground. However, in certain cities, such as Seattle, all decks above 18 inches off the ground require a permit. While most counties follow similar guidelines regarding whether a deck needs a permit, checking with your specific county and city is crucial.

Don’t Forget

Decks that will be higher than 14 feet off the ground, contain multiple floors or will be used to support a hot tub or spa may need to be designed by a licensed engineer or architect. Additionally, a deck built in or near an environmentally critical or shoreline area may need a site visit before obtaining a permit.

Metal components used in deck construction must be hot-dipped, galvanized steel, stainless steel, or zinc-coated and up to ASTM A153 specifications. Finally, any wood used in deck construction must be pressure-treated or possess qualities that make it resistant to decay.

Build Your Dream Deck

Failing to follow the building code when crafting your dream deck can lead to unfortunate consequences. While it may seem as if county code enforcers are trying to rain on your parade, there’s a good reason for the relatively strict requirements for deck building. Improperly constructed decks can collapse during use, causing injury to the individuals using them and property damage. Adhering to building codes ensures your deck is safe and sturdy for years to come.

Anything worth doing is worth doing right. At Blue Sky Decks, our team is familiar with the requirements and permits needed in Idaho and Washington, ensuring you end up with a deck built to code and properly permitted. If the thought of building an up-to-spec deck sounds exhausting, don’t give up on your dream of creating your ideal outdoor entertaining space. Instead, contact Blue Sky Decks today, and let our team of experienced professionals help you from planning to completion.

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