Georgia-Pacific commercial roof fiberboard is used in conventional built-up and modified bitumen systems, as a recover board over existing roof decks prior to reproofing, and as a protective cover over insulation. This uniform-density fiberboard uses cellulosic wood fibers with additives to improve strength and moisture resistance. Available in 1/2-inch and 1-inch high-density thicknesses, and 1/2-inch regular density thickness. For more information, call 800-BUILD GP or visit www.gp.com.