The process and materials used to construct walls and ceilings has been in a constant state of flux for as long as people have been building homes. However, there are a few materials that have stood the test of time and continue to be mainstays in wall and ceiling construction today: plaster and drywall. Though their names are sometimes used interchangeably, these are two different construction materials with their own histories, compositions, and applications. They do share a common purpose: to create sturdy, seamless interior walls and ceilings.
What is plaster?
Plaster is a mud-like composition commonly used in construction for walls and ceilings. It comes in a powder made from a mineral compound like gypsum, and can also be made with lime, clay, or cement. When mixed with water, plaster forms a thick wet paste that helps fortify and smooth a wall’s surface. Plaster is also used for architectural details such as crown moulding, ceiling medallions, and quadrants, which frame features like windows and doors.
The earliest known plasterwork dates to 7,000 B.C., when ancient Egyptians used plaster to line the interiors of houses and tombs. Before World War II, most wall construction used plaster. Builders nailed lath—slim, tightly spaced boards—to wall studs, which they coated with layers of plaster to form a smooth, solid wall. But the plaster and lath method wasn’t efficient, as it required a lot of lumber and time for the thick, wet plaster to dry. During World War II, lumber and labor shortages prompted builders to embrace using drywall for wall construction.
Today, drywall has surpassed plaster as the industry standard for walls and ceilings. Every year, more than 20 billion square feet of drywall is manufactured in North America, according to the Gypsum Association. Plaster is still used for finishing walls, but lath has been replaced with drywall.
What is drywall?
Drywall—also known as Sheetrock, wallboard, plasterboard, or gypsum board—is a panel of gypsum plaster sandwiched between two sheets of paper. Its width ranges from ¼ inch to ¾ inch.
There are four main types of drywall:
- Standard drywall. This affordable drywall comes in a variety of sizes and is most commonly found in residential homes.
- Mold-resistant drywall. This drywall comes covered in fiberglass (not paper) to repel mold and mildew. In the US, it is most commonly used in areas with high moisture, like the West and East Coast or the South.
- Moisture-resistant drywall. This type is ideal for humid areas like bathrooms and laundry rooms.
- Fire-resistant drywall. Made with non-combustible fibers, fire-resistant drywall is required by some building codes, particularly in commercial buildings like hotels.
Drywall is relatively affordable and easy to install. It’s also durable and can last an average of 40 years.