Homeowners and business owners often appreciate the aesthetics of exposed brick walls, or want to reapply plaster so it looks new. In some cases the work entails removing thick plaster layers already covering the brick. It's a messy job, but the plaster must be broken away from the brick surface manually. With care, you can get the plaster off the brick without damaging the brick in the process.
Remove all furniture from the room, or cover the items with dust sheets. Cover the floor surface with dust sheets also.
Fill a hand-held sprayer with water. Spray the plaster wall with the water to keep down the dust when removing the plaster.
Put on a pair of heavy work gloves to protect your hands. Wear safety goggles and a respirator to protect yourself from plaster dust.
Place a chisel point onto the wall at a 45-degree angle, then strike the head of the chisel with a hammer to create cracks throughout the plaster. Lift the plaster up and away from the bricks by wedging the chisel into the cracks then twisting the chisel point slightly to loosen the plaster enough to remove the pieces by hand. Continue until you've cleared the entire surface of the plaster.
Wipe the plaster residue from the bricks using a damp cloth. Allow the brick to dry and then check for any remaining residue. Saturate any leftovers with water. Use a wire brush to remove the substance. Wipe the area with the damp cloth after removal and allow the bricks to dry overnight.
Apply a layer of sealant over the bricks using a paint roller. The sealant protects the bricks from exposure to air and moisture. Allow the sealant two days to dry before touching the newly-exposed brick wall.
Use cardboard cartons to store the plaster for removal from the area. Hang a sheet of polyurethane sheeting from the ceiling to the floor surrounding the work area using masking tape, to prevent plaster dust from spreading throughout the room.
Open windows and doors to the room before sealing the brick to provide adequate ventilation against hazardous chemical fumes.