Moisture Resistant Backing Board

In coastal regions, humid climates, or below-grade spaces, constant airborne moisture warps, swells, and ruins standard gypsum and wood substrates, leading to costly callbacks, rework, and even mold growth. Our moisture resistant backing board is a specialty substrate engineered specifically for these high-humidity, non-saturated environments, delivering long-term dimensional stability where standard panels fail.

This moisture resistant backing board features a closed-cell, water-repellent core formulation, with a full-body moisture-resistant treatment that limits water absorption to under 5% - far lower than standard moisture-resistant gypsum board. Unlike surface-only treated panels, its moisture resistance runs throughout the entire panel, so cut edges and drilled holes maintain the same protective performance, with no risk of moisture wicking into the core. It delivers exceptional dimensional stability, with a deformation rate of less than 0.1% even in sustained 90% relative humidity environments, preventing warping, swelling, and surface cracking that can ruin paint, wallpaper, and other finishes.

It is also engineered for occupant health, with zero added formaldehyde, low VOC emissions, and no toxic additives, making it safe for enclosed spaces like basements, bedrooms, and home offices. Installation follows the exact same workflow as standard gypsum board, with compatible fasteners, joint treatment, and finishing methods, so crews can install it with no additional training or specialized tools. It is ideal for non-splash zones in bathrooms, laundry rooms, kitchens, enclosed balconies, and below-grade basements, as well as multi-family housing projects in humid coastal regions.

Yiheng Holdings Co., Ltd. produces our moisture resistant backing board with strict quality control, testing every batch for moisture performance and dimensional stability. We offer a full range of standard sizes and thicknesses, delivering a reliable, easy-to-install solution for projects in high-humidity climates.