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Ceramic Tile Backer Board Tips

Installation of Ceramic Tile Backer Boards

Keep it Away From the Ledge!

The biggest mistake, that is commonly made when installing any of the tile backer boards, is allowing them to come into contact with the flat ledge of the tub or shower pan. This is a HUGE mistake. In the event the caulk seal between the bottom row of tile and the tub/shower fails, water can get behind the tile. If the backer board is touching this ledge, it will readily soak up this water like a sponge. In fact, because of capillary attraction, the water can actually begin to climb UP the backer board. Given enough water, the situation can become critical. The backer board becomes soaked, it transfers this moisture to the wood framing members, and BINGO, wood rot begins. It can be a serious problem.

The best thing to do is to hold all tile backer boards up 1/4 inch from these ledges. Then, before installing the tile, apply a bead of pure silicone caulk between the backer board and the ledge.Tool the joint with your finger so that no caulk projects beyond the front plane of the backer board. Any excess caulk may interfere with the installation of the ceramic tile. It is also a good idea to caulk all seams where the backer board touches another piece of backer board. This means all inside corners and any other horizontal seams as well.

Manufacturer's Instructions

Virtually every manufacturer of tile backer boards has specific installation instructions. These instructions cover nailing patterns and joint taping. These instructions vary depending upon the product you intend to use. Be sure to obtain and follow these instructions.

Vapor Barriers

When installing any of these products, it is a good idea to install a four or six mil plastic vapor barrier on the wood framing members before installing the tile backer boards. This vapor barrier should actually be installed before the tub or shower pan is installed. It should extend from floor to ceiling. This barrier only takes a few minutes to install and will prevent damage to your home. The Tile Council of America requires this vapor barrier in almost all installations. They have an excellent publication outlining ceramic tile installation procedures. It's called Handbook for Ceramic Tile Installation. It is a wonderful publication that will help you obtain the best possible results on your next tile job.

Manufacturers of Ceramic Tile Backer Boards

  • American Gypsum
  • James Hardie Building Products
  • National Gypsum Company
  • USG - United States Gypsum Corporation
  • Georgia Pacific Company
  • W.R. Bonsal Company
  • Custom Building Products

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