this thicker drywall is the standard for ceilings. Green board is a moisture-resistant drywall that gets its name from the green-colored wax paper backing that gives it its resistance to water.

Also called “greenboard”, mold-and-mildew-resistant 1/2-in. drywall is a somewhat different animal. Manu­facturers use various methods to eliminate or treat the paper that covers the gypsum core.