It's installed the same way as standard drywall. Keep in mind that greenboard is not water-proof . And if your tile is not sealed properly the greenboard may deteriorate from moisture penetration. Concrete Backerboard 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. Furring strips should also be used in a shower that has a shower pan running up the sides. These will make the surface even for the backerboard. Little blocks are used here to hold the backerboard up because a mortar bed still has to be poured over the shower pan. Cutting backerboard is a lot like cutting drywall, except that backerboard is much harder.