COREtec One Plus features our innovative COREtec WPC structure, and an attached cork underlayment for sound absorption. Since COREtec One Plus is 100% waterproof, COREtec floors can be installed in wet areas and will never swell when exposed to water. COREtec One Plus is inert and dimensionally stable; it will not expand or contract under normal conditions. Further, COREtec One Plus never needs expansion strips in large rooms.