Deciding what screws to use for your decking depends heavily on what type of decking you are building.
- Flathead screws are the safest bet for most decking, they have the most holding power of any screw and are often used with pressure-treated decking.
- Trim head screws are excellent for finishing applications or installing fascia boards.
- Truss head screws have an extra wide head that is rounded over the top and are most adept at securing thinner one-ply materials.
- Hexagonal head screws have a built-in washer to distribute their weight. They are great for wood-to-wood applications such as framing, ledgers and joists.
- Cap head screws are best for composite decking fixings thanks to their taller head and reverse thread to prevent mushrooming.
How To Build Composite Decking
Create your dream decking with our advice.
- Measure the area where you want to install the decking.
- Decide on the layout and design. Consider factors like the shape of your space, any obstacles like trees or posts, and where you want access points.
- Clear the area of any debris, rocks, or vegetation.
- Check the ground for levelness. If it’s not level, you may need to adjust or install a base of gravel or sand.
- If building a raised deck, install post anchors into the ground and pour concrete around them for stability.
- Attach joist hangers to the ledger board (if fixing decking to a wall) or to the posts.
- Lay out the joists according to your design, ensuring they are spaced according to the manufacturer’s recommendations (usually around 16 inches on centre).
- Attach the joists to the ledger board or post anchors using appropriate hardware.
- Lay the first decking board along the edge of the frame. Use composite screws to attach it to the joists.
- Use spacers to ensure consistent spacing between boards.
- Continue attaching boards, ensuring they are straight and level as you go.
- If using decking clips, follow the manufacturer’s instructions for installation.
- Measure and cut boards as needed to fit around obstacles or at the edges of the deck.
- Use a saw to make precise cuts, and ensure edges are smooth.
- Install fascia boards around the edges of the deck to cover the ends of the decking boards and create a finished look.
- Attach fascia boards using composite screws.
- Check the entire deck for any loose boards or protruding screws. Secure or trim as necessary.
Where to Screw Decking Boards
Your decking board screws should generally be 1.5 to 2.5 cm from the edge of the board. At the joint where two board ends meet, screws should be 2.5 to 8 inches from the edge.