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USG Durock® Brand Cement Board with EdgeGuard™ is a backerboard for tile and exterior finish systems. Its enhanced proprietary edge performance prevents spinout and crumbling. It is easy to cut and fasten, is water durable and mold resistant and is warranted for interior and exterior applications. Its classification number according to the UNCPC classification system (see http://unstats.un.org) is 37560. USG Durock® Brand Cement Board with EdgeGuard™ offers architects, builders and tile contractors a strong, waterdurable tile base for tub and shower areas. It is also an ideal underlayment for tile on floors and countertops in new construction and remodeling. The board is readily applied over wood or steel framing spaced 16 in. (406 mm) o.c. with corrosion-resistant wood screws, steel screws or hot-dipped galvanized roofing nails. After joints are treated, wall or floor tile is applied using latex fortified mortar or Type I organic adhesive. USG Durock® Brand Cement Board with EdgeGuard™ is preferred by many applicators as a base for directly applied finishes, tile, stone and thin brick used in building exteriors. The 1/2 in. (12.7 mm) and 5/8 in. (15.9 mm) panels are Underwriters Laboratories Inc. (UL) Classified for fire resistance and may be used in any UL Design where Type DCB panels are listed.