The History of Drywall
Drywall is an invention of the 20th century. Today, it is an essential part of residential and commercial construction. When was drywall invented? How did it take over as the industry standard?
Before drywall, there was plaster
Plaster has been around for thousands of years. The ancient Egyptians burnt gypsum in open air fires to produce plaster. The Greeks and Romans used plaster for architecture and decorative sculpture. Plaster sculptures were found when excavating the ancient city of Pompeii. Plaster is found throughout middle eastern architecture. The Babylonians lived in houses with plaster walls. The Abuhav Synagogue Tzfat in Israel features extensive plaster work. Plaster is even found in Japanese architecture. Why has drywall replaced plaster in most construction applications? How did this transition take place?
In the early 20th century in the United States, plaster was used extensively in residential homes. To plaster a home, thin strips of wood were nailed over bare studs. When installing wood lathing, a quarter inch to a half inch gap was left between each strip of wood. A base coat of plaster was then spread over the lathing to create a foundation. The base coat of plaster was pushed through the gaps between strips of lathing to anchor it to the subsurface. As the base coat dried, it created what are known as keys, that hold the plaster in place. Finally, one or two finish coats of plaster were spread over top to smooth out any imperfections. The finished plaster was anywhere from 5/8 to 3/4 inches thick.
The U.S. Gypsum (USG®) company invented drywall in 1916. It was first sold as small tiles for fireproofing areas. Within a decade it took on the form that we are familiar with today; one compressed layer of gypsum between two thick sheets of paper. Later USG® began selling drywall under the well-known brand name Sheetrock©. Most builders however were slow to use the new material. Plaster had been around for millenniums. What would cause builders to start using drywall?
When drywall first started catching on in construction, it was often used together with plaster. Quarter inch thick sheets of drywall were used as replacements for wood lathing. Once drywall was installed over the bare studs, one or two thin layers of plaster were spread over the entire surface. In this way, the finished surface was still completely made of plaster. As drywall technology improved, it became possible to paint drywall directly without needing a skim coat of plaster. Today, only the joints where two sheets of drywall meet are taped and finished to create smooth walls.
Less labor means lower cost
The labor involved in traditional plaster work is considerable. However, with drywall, a journeyman hanger can cut large sheets of drywall to size, and nail or screw them into place. Rather than troweling the entire wall with two or three layers of plaster, a drywall finisher only needs to tape and float the seams, corners, and nails. The labor involved in plaster work can be as much as 4 times that required to hang, tape, and finish drywall. As a result of the increased labor involved, plaster work is much more expensive than drywall. This is the primary reason that more and more builders started using drywall in new construction.
Following WWII, several factors combined to create a real estate expansion that accelerated the use of drywall. Following the devestating effects of WWII which came on the heals of the Great Depression, many people desperately desired a return to the ideals of pursuing the American Dream. The Housing Act of 1949 facilitated the construction of thousands of homes across the United States. In addition, with the developement of the Interstate Highway system, more and more people were moving to the suburbs. It was in this context that Drywall took over as leader in the industry. By the late 1950's and 1960's, though plaster was still found in new construction, drywall was begining to be used at an increasing rate.
Drywall takes over as the industry standard
Drywall continues to improve. Today you can purchase sheets of drywall in almost any size needed. In addition to the variety in lengths and widths available there are different types of gypsum board for different applications. Fire retardant drywall panels are used in nearly every type of construction. There are drywall panels that can hold up in increased moisture conditions. There is drywall that resists mold growth. There is drywall that resists indentation for use in high traffic or high abuse areas. There is drywall specifically designed for elevator shaft application where fire protection is extremely critical.
Is Plaster Dead
Plaster work is still needed in certain applications. Though it is more and more difficult to find skilled tradesmen who can do plaster work, their talents are still in demand. Today, plaster is primarily used in commercial and industrial building construction in limited applictions. Stairwells in industrial buildings are common areas for plaster since they are often built using cinder block or poured concrete walls. A layer of plaster is spread directly over the concrete to create smooth walls. Areas of high moisture are other possible applications for plaster since it holds up better in these conditions.
The years ahead will certainly bring advances in technology and materials that will likely make their way into the realm of construction. Will anything replace drywall as the industry standard for interior finishing? It is possible, and only time will tell.