Sheetrock is to gypsum boards as Xerox is to copy machines. Sheetrock is a registered trade name of certain gypsum boards. And while drywall is the process of installing those boards, sometimes the boards are called drywall as well. Gypsum boards go by many other names, such as wallboards and plasterboards.
Gypsum boards or drywall are formed from flattened gypsum sheets that are sandwiched between heavy paper. While these kinds of panels were introduced in the late 1800s, their rise in popularity began after WWII. Prior to that, walls were often made of wooden structures covered in plaster.
These boards are familiar sights in new construction or remodeling. Their smooth surfaces are paneled together, connected with taping and joint compound, and finished in a variety of decorative ways, the most common being texturing and paint. Alternative finishes are ceramic, plastic, metal tile, wall paper, and panels.
Gypsum is a mineral that is mined or quarried and then transported to manufacturing facilities. There it is crushed to powder, heated, and some intrinsic water is removed in the process. After that, it is remixed with additives and water to form a slurry that is fed between layers of paper and formed into the distinctive boards.The paper bonds to the core slurry, the boards are cut to length, and then dried.
There are different ratings for drywall. The ratings have to do with the thickness and the amount of fire retardant, which is created from noncombustible fibers or minerals added to the slurry when it is formed into boards. The different thicknesses and ratings of the boards can be strategically used as tools in sound reduction and fire control. Gypsum boards can be used to create extra fire-resistant layers in structural areas, such as stairwells and shaft walls. The application of thicker boards provides better impact resistance and higher rigidity. Some are abuse resistant, standing up against surface indentation. Thinner boards can be used for curved surfaces. Special lengths and widths are available for special applications. There are a variety of edges that finish the boards, to create a variety of effects.
Gypsum boards are not recommended where there is continuous high exposure to water or humidity. This refers to swimming pool enclosures, saunas, or similar constructions. If gypsum is exposed to floodwater it needs to be replaced, as contaminants will dry inside the boards.
Gypsum boards can be attached to light weight metal framing. One of the advantages of metal framing is that it does not run the risk of shrinking, like green lumber. As lumber dries and shrinks, it can affect the final look, as “nail pops” are created, exposing nail heads as the lumber shrinks. Thus gypsum boards are the perfect complement to metal framing.