Drywalling – What Is Drywall?
If your house was built in the last 50 years or so, there’s a very good chance that all of the walls and ceilings are covered with drywall.
Drywall is essentially the modern alternative to hand-applied wall plaster and has all but replaced plaster in new home construction.
When it’s time to choose a material to cover the framing on your interior walls and ceilings, the low cost and relatively DIY-friendly installation of drywall make it hard to beat.
How Drywall is Made
Drywall and plaster (and plaster of Paris) share the same main ingredient: gypsum.
Gypsum is a natural, nontoxic mineral that is mined in 85 countries around the world.
Its chemical makeup consists of calcium, sulfur bound to oxygen, and water.
Gypsum crystals are ground into a fine, white power that binds into a solid mass when mixed with water.
In addition to mined gypsum, drywall can be made from “synthetic” gypsum derived from flue-gas desulfurization (FGD), a process of cleaning smokestacks in coal-burning power plants.
Tapered edges of drywall panels
A drywall panel consists of a gypsum core wrapped in several layers of paper (typically recycled paper).
During manufacturing, a slurry of dense liquid gypsum is poured onto continuous sheets of paper.
This is followed by a center layer of aerated gypsum and topped with another dense layer of gypsum before more paper is sandwiched on top.
The sheets are extruded for a uniform thickness and to create a taper along the long edges.
Short edges are cut to create the various lengths of panels.
The front paper of the panel is called the face paper and is usually white.
Back paper is usually a light brown, similar to butcher paper.
A Brief History of Drywall
Drywall was originally known as Sackett Board, after its inventor, Augustine Sackett.
It was patented in 1894 and was intended as a labor-saving substitute for traditional plaster.
In 1909, Sackett’s invention was bought by the US Gypsum Company (USG).
Which remains North America’s largest producer of drywall panels today.