drywall

Drywall, also known as gypsum board or plasterboard, is a panel used to construct interior walls and ceilings. It consists of a gypsum plaster core encased in sheets of paper or a similar facing. The most common size is 4 by 8 feet, with thicknesses typically 1/2 inch for walls and 5/8 inch for ceilings or fire-rated assemblies. Specialty boards exist, including moisture-resistant varieties (often called green board or purple board) and fire-resistant Type X boards, as well as cement boards for wet areas.

Manufactured by pressing gypsum plaster between two sheets of paper and heating to set, drywall panels are produced in long lengths that can be cut to fit. They are installed by fastening to wood or light-gauge steel studs, with panels positioned horizontally or vertically depending on design. Edges are joined and finished with taping and joint compound, then sanded smooth and painted.

Common drywall finishes include standard gypsum board for typical interiors, fire-rated Type X with added glass fibers for increased fire resistance, and moisture- or mold-resistant variants intended for kitchens, bathrooms, or basements. In wet areas, cement boards or moisture-resistant boards are preferred over standard drywall.

Advantages include quick installation, smooth concealed surfaces, and decent fire resistance when used with proper assemblies. Limitations include vulnerability to moisture, impact damage, and potential cracking at joints. Repair typically involves cutting out damaged sections and applying replacement panels with tape and compound.

From an environmental perspective, drywall contains recycled gypsum and can be recycled where facilities exist; disposal should follow local guidelines. Safety considerations include avoiding excessive dust during cutting and, in older buildings, testing for asbestos-containing joint compounds where applicable.