Decking alternatives: a run down on wood plastic composite decking ...16 Sep 2014 ... Typically made from a combination of different materials (namely, wood and plastic), composite boards are processed to have the appearance of timber decking, although it is still up for debate whether this has been perfectly achieved. Types of ... recycled materials, while environmentally friendly, are not chemically designed for exterior use and poor quality recycled HDPE may result in quicker deterioration of the product. ... They come in either hollow or solid boards.