Which type of water-resistant material is often used in bathrooms?

Cement board is the ideal choice for water-resistant applications in bathrooms because it is specifically designed to handle exposure to moisture and humidity. Unlike traditional drywall, which can easily degrade and promote mold growth when wet, cement board is made from a mixture of cement and fiberglass, providing a durable, stable surface that resists water penetration. This makes it particularly suitable for use as a substrate for tile installations in wet areas such as showers and tub surrounds.

Additionally, cement board is non-combustible and more robust than other options like drywall or wood paneling, which can warp or suffer damage from moisture. While vinyl siding is a strong exterior material for moisture resistance, it is not typically used indoors, especially in areas directly exposed to water, such as bathrooms. In summary, the composition and design of cement board make it the preferred material when water resistance is a priority in bathroom construction or remodeling.