Hardie Board, WonderBoard and Durock are all classified as cement boards. These sheet goods are made with a mixture of Portland cement and sand instead of the powdery gypsum that’s used in drywall.

James Hardie® Fiber Cement uses 4 simple and Sustainable Ingredients: Water: Dissolves the wood pulp; activates and hardens the cement. Sand: Creates superior all weather performance and resilience.