How to Install Deck Boards

The deck boards are the major part of a deck and the part that your guests will notice the most, so take care to install them correctly.

Install the deck boards parallel to the house or at an angle. Angles take more work, but the work goes quickly and easily.

Lay a 4-x-8 sheet of 1/2-inch plywood or other hard surface material over the deck joists, leaving some space against the wall. This becomes a working surface until you install some of the boards. Don't fasten the plywood to the joists.

Cut off the ends of a few of the boards at the angle you want (cut at 40 to 45 degrees, but no more) or place the boards parallel to the house.

Measure and cut the first few boards to the approximate length needed to cover the joists. It's OK if the boards hang over the rim joists.

Butt boards together if your deck is large and you need more than one board to cover the length. Stagger the lengths so all the splices won't be in the same spot. Cut the boards so they meet in the center of the same joist for fastening.

Fasten the deck boards to the ledger plate and to each joist--leave a small gap between the deck board and the wall. Use two screws or nails wherever the deck board comes in contact with a joist.

Install the other deck boards parallel to the first board until the deck is covered. Unless you are using raw lumber, place a few of the fastener screws or nails between each board as spacers so there will be a gap for water to drain off the deck.

Take a chalk line and snap a line on any boards that are overhanging the deck. Make the line even with the rim joist. Use a circular saw to cut the boards even with the edge of the deck.

Things You Will Need

  • 1-x-6 or wider kiln-dried or composite deck boards
  • 1/2-inch plywood
  • Measuring tape and pencil
  • Carpenter's square
  • Saw horses or table
  • Circular saw with carbide blade
  • Protective shoes and gloves
  • Disposable particle mask
  • Safety glasses or goggles
  • Hearing protection
  • Angle duplicating tool
  • Cordless drill
  • Hammer
  • Galvanized nails or deck screws
  • Chalk line and chalk

Tips

  • Don't install deck boards tightly to the side of the house. They hold moisture against the wall and cause rot. Gap the ledger plate with washers to prevent water from collecting.
  • Don't leave a gap between the deck boards if you are using lumber that has not been kiln-dried. The gap will occur naturally as the wood dries. Leaving a gap now will cause too much gap later, possibly making the deck unsafe for women's high heels.
  • Deck boards are usually slightly bowed. The high edge is called the crown. Place the crown side up. The boards won't wiggle and will flatten slightly from the pressure of the fasteners.
  • Use screws to install deck boards because they are easier to remove if you make a mistake or need to dismantle the deck in the future. Use galvanized or rust-resistant screws.

Warnings

  • Use a ground-fault circuit interrupter on all power cords.
  • Don't wear gloves while using a circular saw.
  • Wear a disposable particle mask when cutting boards.
  • Use hearing and eye protection when using power tools.