This uniform-density fiberboard uses cellulosic wood fibers with additives to improve strength and moisture resistance. It is available in high-density versions in 1/2" and 1" thicknesses, and regular-density in 1/2" thickness.
Applications include:
Use under fully adhered EPDM single ply membrane (high-density only)
Use under mechanically fastened roof systems
Use under loose-laid ballasted roof systems