Home Repair and Paint Guide

... Cement board provides a very stable surface for ceramic tile. It is thin and installs easily with basic hand tools. The surface provides a high level of grip for tile adhesive. For a top quality ceramic tile job, you need to be sure the backer board is securely attached to the substrate and is flat and level. For walls, this means that there are no bows in the cement board and the edges are attached over, and supported by, the studs. Don’t leave an edge “hanging” - in other words, not supported from behind. On floors, the cement board is attached to the sub-floor material. Make sure the floor is solid and does not flex under load. This is especially true for kitchens where large appliances are installed. Refrigerators are especially problematic because they are rolled into place, heavy, and occasionally moved so the floor can be cleaned. Cement board can be cut with a circular saw driving an abrasive blade, but that creates a ton of dust and can damage the saw motor. It’s better to score the backer board with a hand tool that has a carbide tip. Make several passes along the cut line, and then apply pressure to the other side of the cement board along the scored line. It usually snaps the backer board in two along the scribed line. Cement backer board can be screwed or nailed to the wood framing. Always follow the instructions provided by the manufacturer. Screws are best because they hold tight and don’t loosen over time. Make sure that the screws or nails are corrosion resistant. Leave about a 1/8 inch gap between the boards and fill this gap with silicone caulk. Never install the board with an edge directly touching something like a bathtub rail because water can get into the board and destroy it ...