Let’s start off by stating PVC decking is not Composite Decking.
Composite decking is trying to compete with PVC decking. Composite material is made up of two main components, with a PVC covering. 1. A plastic of any source, usually what ever they can buy cheep. 2. A filler, usually some form of wood, could be hardwood or softwood. It is this combination, that makes this product very susceptible to thermal expansion. Composites need to move, the darker the colour and the more sun exposure, will determine how much it will expand.
PVC on the other hand, is made of virgin material and is full of very small air bubbles. these tiny air pockets service two main functions.
1. They act like insulation and do not allow the product to absorb and retain as much solar heat.
2. The tiny air pockets handle any of the expansion and contraction the material needs. By choosing PVC I am able to make nice tight mitre joints and your deck boards will not shift on you.
There are a few, cost is the big one.
The product itself runs between 5 and 7 times the cost of treated lumber. In reality though, it is only a little over twice the project cost. The under structure will still be treated lumber and the labour for this material is the same. The fact that the PVC is quite costly, the care in handling of the decking is of great concern. Therefor there is a slight increase in the labour cost involved in installation. The next Con for this product is snow and ice in the winter. If you are a year-round griller like myself a deck may be slippery when it is covered in snow or ice. The best way to avoid slipping issues is with a outdoor carpet or runner.
If your looking for a deck that is truly low maintenance and will retain its wow factor for many years, this is the decking product of choice. There is a 35-year fade and stain warranty from the manufacturer. The colour choices are plentiful.
If money was not a concern who would not want a PVC Deck that will look like new 20 years later.