Consumer Affairs rates Trex decking with less than two stars (out of five) based on 45 reviews, many of which cite mold as a problem with their decking. Other complaints include warping, scratching and fading.
About one third of the reviews reported to Consumer Affairs between 2008 and 2015 cite mold as an issue with Trex decking. Several customers claim that mold grew on their decks despite following the instructions by Trex to prevent its growth. Those instructions urge customers to clean dirt, pollen and other debris from the Trex surface with a soft brush, soapy water and a hose. Customers who reviewed Trex decking to Consumer Affairs describe the growth of a black mold that stained the deck surface and continued to reappear despite efforts to clean it.
Trex decking settled a class action lawsuit pertaining to mold issues with their product line in 2014. The lawsuit, filed on Jan. 19, 2009 claimed that some first-generation non-shelled wood-plastic decking made by the company was susceptible to mold growth and violated the company's 25-year warranty. Trex blamed the mold issue on environmental factors such as improperly spaced boards and debris covered decks. However, they agreed to pay $8.25 million to settle the case. Customers who experienced mold problems and bought their Trex decking between 2004 and 2013 were eligible for remediation.