Glossary: Gypsum Board
**Gypsum Board** (commonly known as drywall or plasterboard) consists of a core of calcium sulfate dihydrate (gypsum) pressed between heavy facer sheets of paper, used for interior wall framing finishes.
Drywall Sizing & Thicknesses
Standard gypsum boards are 4x8 or 4x12 feet. Common structural wall thicknesses are 1/2 inches (residential) and 5/8 inches (commercial fire-rated walls).