Composite Deck Board Installation

Composite Materials

• Composite deck boards are a combination of wood fibers and a plastic resin, and are rot-resistant. Manufacturers typically offer a warranty that indicates it is rot-resistant, not rot-free. The wood fibers used in the product are still subject to rotting, but composite decking does not suffer from insect damage as wood products do. Deck boards are molded and some have a grain pattern stamped on the top surface. The material does not require staining or sealing and is available in colors that mimic various wood species.

Handling

• Before installation, the composite deck boards are floppy. Carry deck boards so the width of the plank is vertical, rather than horizontal, to prevent the boards from breaking or cracking. The composite material cuts and machines much like wood. No special blades are required, and a standard carbide framing blade on a circular saw works well. For cutouts around deck posts or columns, use a jigsaw with a sharp, new blade. Sharp blades are important to make clean cuts, because they reduce friction and prevent melting.

Installation

• A screw-down installation places two screws through the deck board at every joist. Composite deck-board screws have a special screw head prevents the composite material from mushrooming around without the need for pilot holes. They are supplied in colors that match the composite decking. Stainless steel wood screws are another option, but may require pilot holes in some brands of boards.
  Hidden clips that attach to the sides of the deck boards and screw into the joists provide another option. The installation leaves the top surface of the boards unmarred by screws and holes.

Wood Versus Composite

• Unlike composite deck boards, untreated wooden boards are subject to insect damage, require frequent staining and sealing and may warp or crack over time. Both products may eventually rot. Treated lumber fades to silver-gray color after exposure to the elements unless it is stained, but it won't rot and insects won't attack it. Treated lumber can be stained, but regular applications to maintain the stained appearance. It is subject to warping or cracking as is any exposed lumber. Composite decking lasts a long time and maintains its color well with no maintenance. Comparable wood products require yearly maintenance, but have a lower initial cost.