Fibgrout PU 2K is a hydrophobic grout based on polyurethane. FIBGROUT PU 2K is a two-component, spray-applied polyurethane foam that creates a seamless, monolithic barrier against water vapor and air. It is a CFC free, polymeric isocyanate based system for producing rigid urethane foam with a nominal core density of 40 kg/m³ by spray process.