Johns Manville CladStone™ Water & Fire Block insulation is manufactured from inorganic fibers derived from volcanic rock. Advanced manufacturing technology ensures consistent product quality, with high-fiber density and low shot content for excellent performance. Noncombustible, with water-repellent properties, it is ideal for exterior cavity wall and rainscreen applications. Available in 4 densities, CladStone 45 (4.5pcf), CladStone 60 (6.0 pcf), CladStone 80 (8.0 pcf) and CladStone 110 (11.0 pcf).