When building or remodeling a home, one of the decisions that needs to be made is what material to use for the walls. There are several options, including drywall, plaster or plywood. One of the options, drywall, consists of plaster made from gypsum formed into a flat sheet and pressed together between two pieces of heavy paper and then dried in a kiln until it is hard. It is known by several names, including Sheetrock, gypsum board and wallboard.
Gypsum is a mined mineral made up of hydrous calcium sulphate. It is widely found in areas where saltwater once existed. Plaster is made with gypsum by heating it to approximately 300 degrees Fahrenheit, which forces out the majority of the water. This reaction absorbs energy, which enables drywall to resist fire - one of the most important attributes of drywall. Plaster is poured in a slurry and sandwiched between paper and then dried hard to create wallboard, also known as gypsum board.
Sheetrock is a trademarked brand name for gypsum wallboard by the building material manufacturer USG. According to USG, the Sheetrock brand holds about 30 percent of the wallboard market in the United States and is the most widely used brand of gypsum panels in the world.
Gypsum Board vs. Sheetrock
Drywall is made up of gypsum. Sheetrock is the brand name for drywall. Those who say "gypsum wallboard" or "Sheetrock" are referring to the same thing.