Terms of the Trade: What Is Type X Drywall? Terms of the Trade: What Is Type X Drywall?
Type X drywall is a fire-retardant option that's 5/8 inch thick, as compared to the standard drywall thickness of 1/2 inch. Because of its greater thickness, denser core, and glass fibers, it doesn't disintegrate in the heat of fire as quickly as standard drywall, and increases a wall's fire rating from 30 minutes to at least one hour. It costs about 75 cents more per sheet than other options, but is a good idea for use at least where it's required by building codes between an attached garage and the house and around the boiler.