Don't assume this decking goes down just like wood. Here are a few important differences to keep in mind. Joist spacing.
Composites will sag if joists are spaced wider than 16 inches on center.
Screw placement. Composites may crumble if face-fastened too close to an edge. TOH
general contractor Tom Silva recommends keeping screws about ¾
inch from ends and edges. At butt ends, he angles the screws slightly toward the joist. Butt-end spacing.
Boards grow longer in hot weather and shorter in cold, so keep an eye on the thermometer during installation, and follow the manufacturer's spacing specs to a T. Edge spacing.
Narrow gaps can easily become clogged, increasing the chance of stains and mildew, and of boards becoming waterlogged and falling apart prematurely. When Tom fastens through the boards' faces, he uses 16d nails to set the between-board spacing. (With hidden fasteners, the spacing is set for you.)MORE: How to Install Composite Decking (How-To Video)