Drywall takes over as the industry standard
Plaster has been around for millenniums. The Ancient Egyptians burnt gypsum in open air fires to produce plaster. The Greeks and Romans both displayed advanced techniques in using plaster for architecture and decorative sculpture. The Babylonians lived in houses with plaster walls. Why, within the last decade, has plaster been 'kicked to the curb' for most construction applications? Why not use plaster as the industry standard?
The history of drywall
The U.S. Gypsum (USG) company invented drywall in 1916. It was first sold as small tiles for fireproofing areas but within a decade it took on the form that we are familiar with today; one compressed layer of gypsum between two heavy sheets of paper. Later USG began selling drywall under the well-known brand name "Sheetrock". Most builders however were slow to use the then new material and methods of finishing interior walls. No-doubt many thought drywall was just a shoddy alternative for the millenniums old technique of spreading layers of plaster over lathing material to create a very hard, smooth, durable wall. A wall covered with drywall sounds hollow, so perhaps some felt that the finish product was of lower quality.
As with most things, price wins out. The labor involved in plastering entire houses is extensive. Today, rather than installing lathing material over the studs a drywall hanger can simply cut sheets of drywall to size and nail (now more commonly screw) the sheets into place. Rather than troweling two or three layers of plaster over lath to a finished thickness of 1/2 to 5/8 inch, a drywall finisher needs only tape the seams and smooth drywall mud over the seams and nails. Now if you were paying somebody to cover the stud walls in your new home and had the choice of \$1.50/sq ft or upwards of \$5.00/sq ft which would you choose?
Most of the increased cost of the plastering process is in the labor. With that in mind it makes sense why, in the 1920's and 1930's when labor costs were relatively lower than they are today, many builders would stick with plaster walls for a time. In WWII when innovation became the accepted norm, more people experimented with Drywall and then of course following WWII and on into the 1950's when houses were popping up everywhere, Drywall took over as leader in the industry. Now it is by far the industry standard.
When drywall was still in its early years and tradesmen where continuing to experiment with technique, drywall and plaster were used together. Rather than using thin strips of wood as lathing over the studs below, a layer of drywall was installed throughout. A plasterer would then spread a thin layer of plaster over the drywall so that the finished surface product consisted mostly of plaster. As drywall material technology improved, the paper on the surface of drywall boards allowed for painting directly without any skim coat of plaster. Today, only the joints where two sheets of drywall meet are taped and finished smooth to create one continuous smooth wall.
Drywall technology has continued to progress rapidly. Today you can purchase a sheet of drywall in almost any size needed. In addition to the variety in lengths and widths available there are different kinds of gypsum board for different applications. Very common in use today are gypsum panels that are rated as fire retardants. There is drywall that can hold up in conditions of increased moisture. 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.
Who knows what the next few years will bring when it comes to drywall material technology and technique. Will anything replace drywall as the industry standard for interior finishing? Whatever the case drywall has been around for decades and continues to improve.