Composite decking products blend waste wood fiber and recycled plastics, adding in waxes, fiberglass, and preservatives to form wood-like boards. Popular manufacturers known for sustainable products and practices of composite decking include Trex, Nexwood, Verenda, Timbertech, and others.
Some composite products last up to 20 years with little maintenance; however, all weather and warping are not unusual. Composite lumber has some of the strength of wood, it looks and feels something like it, can be worked with wood tools, and it uses waste products that might otherwise end up in a landfill.
In terms of green building, the biggest objection to composite decking is that, although it lasts a long time, it is very difficult to dispose of once it reaches its life’s end. This is because its biological components (wood and other cellulose) and "technical" components (plastics, waxes, and fiberglass) are inextricably blended.
In a well-designed recycling system, biological wastes are allowed to decompose naturally, while technological wastes such as metals, chemicals, and petroleum products are filtered out for reuse. So far, there has been no progress in meeting the recycling challenge of composite wood products.
