Durock cement board creates a stable masonry surface for installing tile and natural stone on floors and walls. Durock boards are two-sided. The smooth side of the cement board installs toward the mounting surface of the floor or wall and provides a bonding surface for adhesive. The textured side of the board gives a better surface for thin-set mortar and creates a strong bond between the tile or stone and the installed cement board. Durock cement board can be cut with standard hand tools, but saws with carbide blades also will cut the boards to size.
Measure the length and width of your Durock cement board with a tape measure. Measure the size of the wall or floor area that you need to cover with Durock. If the floor or wall area is smaller than either the length or width of the cement board, you will need to cut the cement board to fit.
Mark the length of the cut on both faces of the cement board with a pencil.
Place the short side of a drywall square against one side of the cement board. Align the blade of the square with the cut mark. Drag the utility knife along the blade of the square to score the face of the cement board. Flip the cement board over and repeat to score the other side of the board.
Set the score line on the edge of a hard, straight surface. Press firmly on the score line to snap the cement board to length.
Slide a wood rasp along the snapped edge to smooth out the cut.
Set the cut Durock board in place. Keep the cement board 1/4 inch away from tub surrounds and 1/8 inch away from wall corners.
Secure the cement board to the floor or wall by placing a 1 1/4-inch wood screw every 16 inches on center with a screw gun with a No. 2 Phillips head adapter. Screws should be 1/2 inch from the edges of the cement board to avoid cracking the board edges.
Install all solid sheets of Durock as described. Maintain a 1/8-inch gap between each piece of Durock.
Measure over from the edge of an installed Durock board to the center of a pipe or other obstruction with a tape measure.
Mark the center of the obstruction on a piece of cement board with a pencil. Deduct 1/8 inch from the length measured to allow for a gap between the pieces of cement board. Measure the diameter of the pipe. Add 1/2 inch to the diameter and mark the size on the Durock board.
Score a circle around the center mark with a utility knife. Hit the Durock in the center of the score line to remove the circle for the pipe. Clean the edges of the hole with a wood rasp. Install the Durock sheet as described.
Spread latex-fortified mortar along each seam between Durock cement boards with a 4-inch spackling knife.
Lay the interior mesh tape into the wet mortar. Slide the spackling knife along the mesh tape to embed it in the mortar. Cut the mesh tape to length with the utility knife.
Set all screw heads slightly below the surface of the Durock cement board before installing tile or natural stone.