New building codes prohibit backing tiles with greenboard, a paper-faced gypsum material traditionally used behind ceramic or metal tiles in high-moisture areas. However, DensShield® Tile Backer from Georgia-Pacific is a glass-mat gypsum panel that has no paper-facing to feed the growth of mold, and is approved by the new guidelines. The material can be scored, cut and installed like regular gypsum or drywall, and hanging the panels requires no special tools.