Moisture-resistant drywall, which has a light-green or blue face paper to distinguish it from other types of drywall (hence the name greenboard or blueboard), is designed to minimize moisture problems. The panels, which are moisture-resistant all the way through, are made to withstand high humidity and low levels of moisture. Moisture-resistant drywall is used mainly in bathrooms, and to cover the bottom 4 ft. of a laundry or utility room or the wall behind a kitchen sink. It is an excellent base for ceramic, plastic or metal tile applied with an adhesive, or for other nonabsorbent finishes such as paint, wallpaper or plastic tub surrounds.Read more...

As a dense material, drywall is a better barrier against fire (and a more efficient sound absorber) than lighter materials such as plywood, but one type of drywall is particularly effective in containing fire. Fire-resistant drywall panels have a gypsum core with special additives and glass fibers that aid in containing fire. On the surface, these panels look the same as regular drywall, except for a stamp that indicates that they are fire resistant. Fire-resistant drywall is a little harder to cut than regular drywall, because the gypsum core is tougher.

"Fire resistance" signifies the ability of a constructed assembly (the wall or ceiling that is covered with drywall) to contain a fire. The fire-resistance rating for each thickness of drywall is indicated with intervals of time: 45 minutes for 1/2-in. fire-resistant drywall, 60 minutes for 5/8 in. and 120 minutes for 3/4 in. The panels can be layered to increase the fire rating. Read more...

When most people think of drywall, they probably picture the standard 4x8 panel that's been in use since drywall first became popular. But this is by no means the only size or type of drywall available today. Panels come in lengths up to 16 ft., in 48-in. and 54-in. widths and in a wide variety of special-use panels, including moisture-resistant, fire-resistant and abuse-resistant panels, 1/4-in. flexible panels, 1/2-in. high-strength ceiling panels, and foil-backed panels. In this section, We'll guide you through the various types, their uses, the thicknesses and lengths available and the framing specifications for each type. With this information, you'll be able to make the right decision about what type of drywall to order when it comes time to plan the job.

Regular drywall 

Regular drywall panels are 48 in. wide and come in a variety of lengths from 8 ft. to 16 ft. (see the image). Panels are available in four thicknesses (5/8 in., 1/2 in., 3/8 in. and 1/4 in.), each with specific applications (and framing requirements). Read more...

During the 1940s and 1950s prefabricated drywall panels gradually replaced plaster as the material of choice for finishing interior walls and ceilings. The earliest drywall panels were used to replace the lath backing in plaster work; they were narrow (16 in. wide) and only 3/8 in. thick. Today, drywall comes in a wide variety of lengths, thicknesses and special-use panels. The low material cost and the large, easy-to-attach panels combine to make drywall the popular choice over conventional piaster.

Plaster-and-lath construction added a lot of moisture to the building, and plastered surfaces had to be left to dry for up to two weeks (depending on humidity, temperature and airflow) before decorating. By comparison, drywall has a low moisture content and the joint compounds used to finish the panels cover only a portion of the surface, not the entire surface, and dry in 24 hours or less. Hence the name drywall (drywall is known by many other names as well, such as Sheetrock — a brand name, gypsum board, plaster-board, wallboard and gypsum drywall).Read more...