FDW8436-U 2" X 150' FIBERGLASS CEMENT TAPE | FibaTape Cement board tape is a patented alkali-resistant fiberglass mesh drywall tape and the only tape that should be used for cement applications with dry or thin-set mortar. This self-adhesive tape is made from the same vinyl-coated fabric that is embedded in the face of some cement boards to give the board added strength and crack resistance.