Quick Tip: Cement Board
Waterproof and very strong—though not too strong for a do-it-yourselfer to manage—cement board is most employed as a backing for tiled walls and floors.
If you’re remodeling or adding a bathroom, use cement board as an underlayment. A bit of hardened mortar is sandwiched between two layers of fiberglass sheets. It cuts and trims like sheet rock, but it provides a waterproof layer under wall or floor tile. To attach it, drill a pilot hole first, then use galvanized drywall screws.
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