By Brent Gwatney
Demand for wood-plastic composite lumber is projected to increase 9.2 per cent in each of the coming years, reaching $5.3 billion US by 2013, says a recent study by The Freedonia Group. It also predicts deck boards will be the leading application.
Composites have become a popular choice for decking around swimming pools and spas, as well as many other residential and commercial applications, due to their splinter-free, slip-resistant surface, and the ability of some brands to resist moisture. These characteristics—combined with durability, an attractive appearance and increasingly appealing environmental traits—have made composites one of the fastest-growing segments in the decking market.
As demand continues to increase, the number of manufacturers and the variety of brands available in the market has grown. To help select environmentally friendly composite decking products and ensure design goals and expectations are met, builders and designers should consider the following characteristics.
Recycled, or not
With more than 40 manufacturers, all wood-plastic composite decking is not created equal. Most are made with a combination of polyethylene (PE) plastic, wood fibre and a variety of additives, which help stabilize the plastic, enhance colour and protect the decking from ultraviolet (UV) damage, mould and mildew. However, despite using the same or similar ingredients, each manufacturer has its own product formulation and processing technologies.
The use of recycled content, for example, is not universal. Some manufacturers use only virgin materials, while those that incorporate recycled content vary greatly in the amounts used. Some manufacturers claim their products include recycled material, but often omit the details on the overall percentage and specific amounts of pre- and post-consumer content. It is important to keep this in mind and find out the actual percentages. The amount can range from zero to approximately 95 per cent (additives and colour agents are typically included, preventing decking from being considered 100 per cent recycled content).
In addition to verifying percentages, determining whether the recycled materials come from pre-consumer or post-consumer channels will also help in selecting the most environmentally friendly product. Pre-consumer materials are generated by manufacturers and processors and may consist of scrap, trimmings and saw dust. Post-consumer material is waste that has been used and disposed of by consumers and diverted from landfills (e.g. detergent containers, milk jugs, plastic bags or film).
Post-consumer waste is harder to obtain and recycle, thus it is more likely to end up in a landfill. For these reasons, composite decking containing post-consumer recycled content is considered to be more environmentally friendly. Composite decking with a substantial percentage of post-consumer content can even help contribute toward green building rating points in Leadership in Energy and Environmental Design (LEED) programs.
For additional information on a product’s environmental background and the manufacturer’s commitment to being ‘green,’ visit their website or read through product literature to understand their processing practices and what they are doing as a company to minimize their impact on the environment. If a company is doing what it claims, there should be information to support their ‘green’ claims. Researching brands will also help determine the history and track record of their products.