1/4"-3'x5' HARDIE BACKER, EZ GRID | 1/4"- 3' x 5' HardieBacker is the original fibre cement backer board. Made of 90% premium Portland cement and sand, it is the underlayment that best protects against damage from moisture and mold behind walls, floors and countertops. Its strength, ease of installation and durability make it the ideal product for wet area applications. HardieBacker is the superior choice among other cement, glass mesh and gypsum boards for tile, vinyl, carpet, and wood flooring installation. Superior strength and durability so floors/walls are stable. Recognized for use in non-combustible construction. Moldblock Technology: achieves perfect score on industry mold tests. Easy to install - score and snap upward.