Concrete Backerboard Concrete backerboard is usually used as an underlayment for ceramic tile . It can be used on walls, floors or countertops. Concrete backerboard has a solid concrete core and is faced on both sides with fiberglass. It's an ideal underlayment for wet areas like shower walls and bathtub surrounds.
Some backer board is a bit thinner than drywall.
If your backer board meets a drywall surface, you may have to first fur out the studs with strips of builders felt to make the surfaces flush. Cutting Concrete Backerboard Cutting backerboard is a lot like cutting drywall, except that backerboard is much harder. Using a framing square, score your cut line a few times. You can use a regular utility knife for this, but you'll go through a lot of blades. A special carbide-blade cutter works better.