A type of moisture-resistant drywall with a green-colored paper facing, designed for use in areas with moderate moisture exposure such as bathrooms and kitchens.

Greenboard is a type of moisture-resistant drywall that features a green-colored paper facing and is specifically designed for use in areas with moderate moisture exposure such as bathrooms, kitchens, laundry rooms, and other spaces where humidity levels are higher than normal living areas. This specialized wallboard consists of a gypsum core treated with moisture-resistant additives and covered with green-tinted paper that has been chemically treated to resist moisture absorption and mold growth. While greenboard provides better moisture resistance than standard drywall, it is not waterproof and should not be used in areas of direct water contact or high moisture exposure such as shower surrounds or areas that will be tiled.

The primary purposes of greenboard include providing moisture resistance in areas with elevated humidity levels, serving as a substrate for paint and wallpaper in moisture-prone areas, offering improved mold and mildew resistance compared to standard drywall, creating a suitable base for ceramic tile installation in dry areas of bathrooms, providing dimensional stability in fluctuating humidity conditions, and offering cost-effective moisture protection for residential and light commercial applications where full waterproofing is not required.

Composition and manufacturing of greenboard involves a gypsum core similar to standard drywall but with moisture-resistant additives mixed into the gypsum slurry, green-tinted paper facings that are chemically treated with moisture-resistant compounds, special adhesives that bond the paper to the gypsum core while maintaining moisture resistance, and manufacturing processes that ensure consistent moisture-resistant properties throughout the board.

Fun Fact: Greenboard was developed in the 1960s as one of the first attempts to create moisture-resistant drywall for residential bathrooms. The distinctive green color wasn’t just for identification – it actually came from the chromium-based chemicals used to treat the paper facing for moisture resistance. While newer products have largely superseded it, greenboard represented a significant advancement in making homes more durable and mold-resistant.