Composition
Drywall is made out of gypsum, a word which may not mean much to you. Gypsum itself is made out of the chemical calcium sulfate, a common mineral that occurs naturally in the earth. To form drywall, manufacturers add additional ingredients that make the drywall construction worthy.
Formation
Drywall is mixed wet, wrapped in heavy paper, then fired in a large kiln to dry. The resulting board is only semi-flexible, quite firm and somewhat water-permeable.
Uses
Drywall is used in construction all over the world as the final layer of interior walls. The large, smooth boards are ideal for their ease of installation and the finish that they provide for paint and wall hangings.
Size
Most drywall boards are 4 by 8 feet and 1/2-inch thick. Some ceiling varieties are 5/8-inch thick.
Features
One reason for drywall's popularity in construction materials is its function as a fire barrier. While one should not depend on it as a firewall, it still functions very well to contain flames and prevent rapid spread of a fire.
Types
As with nearly any construction material, drywall comes in a variety of forms. Some drywall manufacturers sell fire-resistant, mold-retarding, humidity-resistant, sound-rated, sound-proof, recycled and a variety of other specialized types of drywall.