Preparation

• 1). Measure the floor and dry lay the Hardibacker before determining any cuts that need to be made. Make sure none of the board edges end on a subfloor seam, and allow a 1/8-inch gap between all Hardibacker cement boards as well as the walls and cabinets.
  
  
• 2). Mark any cuts that need to be made, using a straightedge to ensure uniform cutting lines.
  
  
• 3). Cut the Hardibacker cement boards by scoring along a straightedge with a carbide-tipped scoring knife and then snapping the board along the line.
  
  

Floor installation

• 1). Apply a layer of thinset where the first Hardibacker cement board will be installed, using a ¼-inch notched trowel (the same size trowel you will use for the tile installation).
  
  
• 2). Lay the first panel of Hardibacker onto the thinset, pressing evenly.
  
  
• 3). Screw the Hardibacker into the floor, using 1¼-inch backerboard screws and using one screw every 8 inches. Offset the interior screws so they are staggered with the outer screws, and make sure no screws are closer than two inches from the edge. (Three-by-five Hardibacker sheets have dots to indicate where the screws should be set).
  
  
• 4). Repeat the process until the entire floor is covered by Hardibacker cement board and ready to tile.
  
  
• 5). Prior to laying the tile, apply a layer of thinset onto any seams in the area you will be working in and press a strip of 2-inch cement backerboard tape firmly over the seam. Continue this procedure as you work across the room.