Gypsum Board

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Gypsum Board

What is Gypsum Board?

A panel made of gypsum plaster pressed between two thick sheets of paper, commonly known as drywall or wallboard, used for interior walls and ceilings in residential and commercial construction.

Description

Gypsum board is a panel made of gypsum plaster pressed between two thick sheets of paper, commonly known as drywall, wallboard, or sheetrock, used extensively for interior walls and ceilings in residential and commercial construction. This versatile building material revolutionized interior construction by providing a smooth, paintable surface that can be installed quickly and economically compared to traditional plaster walls. Gypsum board consists of a core of set gypsum (calcium sulfate dihydrate) sandwiched between paper facings, creating a fire-resistant, dimensionally stable panel that serves as both a structural and finish component in modern building construction.

The primary purposes of gypsum board include providing smooth interior wall and ceiling surfaces ready for paint or other finishes, creating fire-resistant assemblies that help contain fires and protect structural elements, offering sound control through mass and specialized acoustic formulations, providing thermal insulation properties that contribute to building energy efficiency, enabling rapid interior construction with standardized installation methods, accommodating building movement through flexible joint systems, and serving as a substrate for various wall coverings including paint, wallpaper, and tile in dry areas.

Composition and manufacturing of gypsum board involves mixing calcined gypsum (plaster of Paris) with water and additives to form a slurry, spreading this mixture between continuous sheets of paper on a production line, allowing the gypsum to set and harden through a chemical reaction that converts it back to gypsum dihydrate, cutting the continuous board to standard lengths, and drying in kilns to remove excess moisture and achieve final strength and dimensional stability.

FAQs

  • What is gypsum board?

    Gypsum board is a panel made of gypsum plaster pressed between paper sheets, commonly called drywall, used for interior walls and ceilings in construction.

  • What are the standard sizes of gypsum board?

    Standard thicknesses are 1/4″, 3/8″, 1/2″, and 5/8″, with 4-foot width and lengths of 8, 9, 10, 12, and 16 feet being most common.

  • What is Type X gypsum board?

    Type X is fire-resistant gypsum board with glass fibers and additives that help it maintain integrity longer during fire exposure, required for fire-rated assemblies.

  • What’s the difference between regular and moisture-resistant gypsum board?

    Moisture-resistant board (greenboard or purple board) has a treated core and facings to resist moisture better than regular board and is used in humid areas like bathrooms.

  • How is gypsum board installed?

    Gypsum board is installed by fastening to framing with screws or nails, then joints are taped and finished with joint compound for a smooth surface.

  • Why is gypsum board fire-resistant?

    Gypsum contains chemically combined water that releases as steam when heated, keeping temperatures lower and providing fire resistance to building assemblies.

  • Can gypsum board be recycled?

    Yes, gypsum board can be recycled into new gypsum products, and many manufacturers offer take-back programs for construction waste to support sustainability.

Fun Fact

Fun Fact: Gypsum board was invented in 1916 by Augustine Sackett, who originally called it “Sackett Board.” However, it didn’t become widely popular until after World War II when the housing boom created demand for faster construction methods. The term “drywall” came from the fact that it eliminated the “wet” plastering process, and today over 20 billion square feet of gypsum board are produced annually in North America alone!

CSI Code

09 29 00

NAHB Code

920