John, this is a great question, one our customers frequently ask at Ecohaus. We’ve chosen not to offer plastic composites (even those made from recycled materials) for a number of reasons. Real wood decking looks beautiful and natural in a way that plastic composites simply can’t match. Tropical woods like Ipe or Tigerwood (our favorite at Ecohaus) are extremely dense and naturally moisture, rot and insect resistant. They also have better structural ratings than most composite decking options because they are less affected by temperature changes. Some wood is even naturally fire resistant (like our class-A rated cedar decking).
While composite decking technology has advanced over the last few years, it does have some drawbacks that most people may not be aware of, most of which John points out in his post. Options that include wood fiber can be worn down over time, exposing the wood fibers and resulting in small specks of mold growing over the surface. Plastic decking will also fade over time, especially those in direct sunlight. Another problem with plastic composites in direct sunlight is that they can become too hot to touch and have even been known to bend or warp.
However, the biggest reason that natural wood decks are better than plastic composites is that they can be recycled or composted at the end of their life. Because most plastic decking is a composite material made of multiple ingredients (not just plastic) it is nearly impossible to recycle and will likely end up in a landfill.
Of course, it goes without saying, that one should always use sustainably harvested woods. All of our decking options are FSC certified. However, the concern about transportation is still valid. And while I don’t have a life-cycle analysis available to compare the full difference between wood and composite decking, keep in mind that plastic composites require a lot of energy to make and output a lot of emissions in the manufacturing process, which traditional wood decking does not. And of course, depending on where you live, even composites made in the U.S. have significant transportation impacts, including transporting raw materials to the factory and shipping finished product to retail stores.
Read the whole thread on EcoMajority.com here: What to deck with?