Nov 12, 2019 · USG Durock Brand Cement Board with EdgeGuard offers architects, builders and tile ntractors a strong, water-durable tile base for tub and shower areas. Also an ideal underlayment for tile on floors and untertops in new nstruction and remodeling. Board is readily applied over wood or steel framing spaced 16 in. on center with rrosion-resistant wood, steel screws or hot-dipped galvanized