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How Composite Decking Works


Composite Decking Material

There are three types of composite decking material: polyethylene-based, polypropylene-based and nonwood plastics. Oil-based polyethylene and polypropylene composite decking contain some wood. The industry seems to be moving away from polyethylene-based composites to focus on the polypropylene-based product (which is typically stronger and less susceptible to expansion and compression) or polyvinyl chloride (PVC)-based product. These plastic­s have no wood content, do not stain or absorb water. Technology is enabling manufacturers to give all these composites a look and feel that approximates real wood. [source: Descoteaux].

A variety of factors come into play when you're choosing the material for a composite deck, such as cost, availability of color and a hidden fastener system. Composite decking is more expensive than wood, but how much depends on the particular product. Nonwood plastics are significantly more expensive than real wood, are lighter than the other composites, and typically don't contain any recycled content.

The color and desired textures of the deck, where the deck is located and how the deck will be used will help narrow down which the best product [source: Decks].

Some of the big manufacturers are ChoiceDek, EON, Epoch Evergrain, GeoDeck, LP Weatherbest, TImberTech, Trex and Veranda. The industry is evolving, with efforts being made to eliminate some of the stain, fading and mold issues that composite decking has been known for. Here are details on some of the products:

  • CorrectDeck is made from hardwood fiber and polypropylene, with 80 percent of its content from reclaimed or recycled material. Its CX line has a top layer of polypropylene that encases the decking with antimicrobial protection to help resist mold and mildew. [source: Descoteaux].
  • Cross Timbers composite is made from oak and polypropylene for a stronger board, which can span 24 inches on center, further than most composite decking
  • GeoDeck's Tongue & Groove includes cellulose with lower amounts of lignin, which makes the product fade-resistant.
  • Veranda's decking has a different combed finish on each side of the board, giving buyers two looks to choose from.
  • EON is 100 percent plastic. The manufacturer uses ultraviolet light inhibitors to eliminate fading. The product has a T-clip to fasten the decking, not nails or screws, giving the finished deck a clean look.
  • Epoch Evergrain looks more like wood than other compression decking, thanks to the use of compression molding to form the product, giving it a deep grain.
  • ChoiceDek's polyethylene and recycled wood decking is lighter and stiffer than some others because of a ribbed design that allows more air circulation between the decking and framing.
  • Many decking companies offer hidden fasteners that are easy to install. Latitudes Composite Decking uses a hidden fastener system that automatically spaces boards with the proper gap [source: Montenegro].

For particulars about installing composite decking, read on.