There’s no shortage of handy hacks and pro tips online for DIY deck building. You’ll find plenty of deck plans, material calculators, and other helpful tools to get you started. It can be fun to plan the shape of your deck and pick out where you want to build it. Shopping for the best materials to build with may not be fun, but it can be interesting and give you insights into new ideas for your unique deck.
Building a deck yourself is most often a rewarding experience, and you will have fun using it season after season if you build it right. But what isn’t so fun is getting the necessary permits and learning the unique local building codes. Fun or not, going through the permitting process will ensure your DIY deck is safe and complies with your area’s requirements.
Deck Building Terminology
Most local governments adopt and adapt the International Building Code (IBC) requirements to their locale. Codes change, and city and county building regulations may not be published accurately—reach out to your local permitting office and ensure you have the latest and most complete requirements for your project. Understanding local building codes is easier if you know a few standard deck-building terms and how they affect your plans.
Grade
The grade simply describes the ground level outside of the deck area. Attached decks and others will typically be more than 30 inches above grade, requiring safety rails. Floating decks are usually much less than 30 inches above grade and often don’t require rails.
Guardrail
Guardrails are the “walls” of your deck that guard against someone falling off the deck. For most decks, any deck area with a drop-off requires a guardrail that meets specific safety standards.
Handrail
Handrails are required for deck stairs and must meet standards specified by your local building department and the IRC. The top of the rail must be between 34 and 38 inches above the nose of stair treads, for example. Your local building codes will dictate spacing between handrails, how the handrail is secured, and other particulars.
Baluster
Balusters are the posts that make up your deck’s hand and guard rails and must be spaced safely. The balusters require specific installation to prevent people from falling off your deck through or under guardrails.
Rise
The distance between one stair tread and another is known as the rise. The rise of deck stairs must meet specific codes, and stairs with more than four rises require handrails.
Now that you can converse intelligently about deck building, it’s time to dig deeper. Most building codes are in place for safety reasons, and some components of your deck are more accident-prone than others. These components fall under some of the most specific and strict building requirements.
The Big Three Deck Safety Components
While local building requirements will vary, you can expect an almost universal code for three important deck components. Framing and footings don’t often cause a deck to fail inspection, but these critical deck areas can make or break your new deck.
Deck Guardrails
Most residential decks require rails that are a minimum of 36 inches above the deck level. You can build higher guardrails and still pass inspection. Again, decks under 30 inches above grade don’t require rails, but they must still meet the code if you use rails.
Deck Stairs
Deck stairs on most decks need rails 34 to 38 inches measured from the top of the rail to the tread. Stair treads must be 10 inches deep or more and support 300 pounds per four square inches. The rise between treads can’t be more than 7-¼ inches.
Deck Balusters
Balusters are infamous for trapping babies’ heads, so the code requires them to be four inches or less apart. Why four inches? That’s the average diameter of a baby’s head! Balusters must also withstand 50 pounds of concentrated load to pass inspection.
So what should you do with these deck-building terms, rules, and regulations? You should learn the information well enough to create and present a permit-ready deck plan to your local building department.
A Building Permit is a Plus, Not a Pain
Local building laws requiring a permit for your new deck may seem overkill, but it’s more of a practical matter. There’s no better way to ensure your deck is safe and built to last for years than having it inspected by a professional. When applying for your permit, you submit your deck plans to ensure they comply with local zoning and construction regulations. Your plans will also be reviewed by a building professional who will determine if your deck meets local building codes.
Most local building inspectors will inspect your footings before they’re poured, the framing before the decking goes down, and the completed deck. Your building inspector may require more inspections at specific intervals of the build, but you can count on at least three inspections. Being at the inspections and interacting with the building inspector is a good practice to ensure timely communication.
Most decks require a permit, and opting out is not an option. At the very least, building a deck without a permit can detract from your home’s value when it’s time to sell. Some DIY deck builders have had to demolish all their hard work or experienced injuries during construction. Worse-case scenarios can also happen long after your deck is completed if it isn’t built to code. According to the Consumer Product Safety Commission, the collapse of decks and similar structures have caused nearly 3,000 injuries—and even death.
Safety and longevity aside, building a deck or other structure on your property without a permit can cost you down the road. More and more communities are using software that captures and compares photos of local homes and other properties year to year. The results allow cities and counties to assess property values more precisely for tax purposes. They also reveal new structures like your deck!
