For proven reliability, install your tile with the 2’ x 4’ x .5" Wedi Board. This building board is lightweight, durable and compatible with virtually any stable substrate. The waterproof polystyrene core is reinforced with fiberglass mesh on both sides and coated with synthetic polymer resin mortar which penetrates the mesh layer resulting in panel strength and exceptional adhesion to thinset mortar. This Wedi Board is thick enough to use as building material when constructing seats and benches in showers.