FIBEROCK® Aqua-Tough™ underlayment is a unique fiber-reinforced gypsum product designed for use under ceramic or porcelain tile, resilient flooring, vinyl, carpet, hardwood flooring, and laminate flooring in wet or dry areas. It has an integral water-resistant composition that offers durability, superior performance, and exceptional tile bond that is not susceptible to the same warping often found in traditional wood underlayment.