How to Install Backer Board

Installing cement backer board isn't as difficult as most homeowners think. Cement backer board is a drywall-type product used as a waterproof base for installing ceramic tiles in your bathroom. The concrete in the backer board isn't affected by water that may somehow seep behind the ceramic tiles. There are many different types of backer boards, with the cement board being the most popular. The one drawback to concrete backer board is that they're quite heavy and thus can be problematic to cut [source: Carter]. We are now ready to learn how to install backer board in your bathroom.

Materials needed:


  • Backer board
  • Trowel
  • Nails or screws
  • Saw
  • Hammer
  • Thinset adhesive
  • Fiberglass tape
  • Tape measure

Here's what to do:

  1. Calculate how much backer board you will need by measuring the length and width of the area you will be tiling. Multiply these two numbers to calculate the area's square footage (square meterage). Each sheet of backer board covers 15 square feet, as each one is 3-by-5 feet. Divide the square footage (square meterage) of your walls by 15, and round off your answer to the nearest whole number. You now know how many boards you need.
  2. Prepare the room by removing any old flooring.
  3. Apply a thin layer of thinset adhesive to the sub floor where you are going to put the backer board. Use the trowel for this. Make sure the entire sheet will have adhesive on it. Press the backer board onto the adhesive.
  4. Nail or screw the backer boards to the sub floor, so that the backer boards won't move at all. Make sure you use corrosion resistant screws or nails.
  5. Cover all the seams between the boards with fiberglass tape [source: Do It Yourself].