Lighter Backerboard. U.S. Gypsum has replaced its Durock backerboard with a version called Durock Next Gen. Perlite filler material makes the new cement board 25 percent lighter than the original — each 1„2-inch sheet weighs 36 pounds. The company says the new board also scores and snaps more easily for faster installation. A 3-by-5-foot sheet costs $9. USG, 800/874-4968, durocknextgen.com.