How to Install Cement Backer Board on a Kitchen Floor

When remodeling the kitchen, you need to start from the ground up. Before you do any work on the walls, you need to install the subfloor and tiles so that they won't interfere with the drywall if you need to raise the flooring. Cement backer board, also known as Hardie Backer Board from one of the manufacturers, provides a solid surface that won't warp.

Difficulty: Moderately Challenging

Instructions

Things You'll Need:

• Measuring tape
• Jigsaw
• T-square
• Thin-set mortar
• Drill
• Fasteners
• Silicone caulk
• Chalk line

1. Put in any necessary plumbing between the beams of the floor and cover with plywood.

2. Measure pieces of cement backer board for the space.

3. Cut the backer board using a jigsaw with a carbide blade. This raises a moderate amount of dust. The carbide blade doesn't have teeth. Instead, it has a rough coating of tungsten carbide, which is extremely hard.

4. Put down a layer of thin-set mortar compound and put the backer board in place, leaving 1/8 inch between pieces.

5. Follow the manufacturer's directions on the type of fasteners to use to connect the backer board to the plywood floor beneath. Be sure to drive the fasteners below the surface of the backer board.

6. Fill the gap between pieces with silicone caulk.

7. Snap base lines with a chalk line to prepare the surface for you to install tile.

Tips & Warnings

• Don't try using a circular saw with an abrasive blade to cut the backer board. That process creates clouds of choking dust and it also can damage the saw motor.