An uneven substructure. Use a flat tool to clean out gaps between boards. If gaps are inadequate, a kerf cut may be required. Ice buildup can occur on Trex as well as other decking materials during extreme weather conditions or because of water puddling combined with freezing temperatures. Calcium chloride, available in many home centers, is an effective treatment for melting ice on Trex and is less messy than rock sa lt.
Phosphoric acid is an ingredient contained in many common products such as carbonated colas.