- Cutting backer board, especially gypsum-core backer board, is done with a simple razor knife. Score the surface with the razor, then snap the board, creating a clean line.

I witnessed first hand what happens when cement backer board is installed without a moisture barrier. Last month I demolished a 25-year-old bathroom that had waterlogged cement board in the shower.

Many builders do not use cement backer board because it is heavier to work with and more difficult to cut than standard wallboard. You should be able to find it at your home center store. If not ...

What was more surprising was that cement based backer boards were available when this home was built and this green board use reflects a cost-cutting measure that is usually a mistake.

Q DEAR TIM: I'm getting ready to buy backer board for a ceramic tile project. Which types would you use and which would you avoid? You've mentioned using cement backer board; do you still feel ...