Plaster is an extremely hard material commonly used on walls to create an artistic effect. Although attractive, it is also very hard to clean and may eventually need to be replaced. Removing that plaster once it is put on your wood walls, however, can be a complicated process. Because the plaster is so dense, it can be difficult to get it off the walls. Be prepared for some hard work when you start this project.
Remove the baseboard and ceiling trim by gently prying it away from the wall with a pry bar. Be careful that you don't splinter the edge of the trim with the pry bar. Set all the trim to the side.
Score the plaster with a sharp heavy gauge utility knife. This cut should be made in a location where you can work comfortably. Throughout the process of removing the plaster from your wood walls, you will need several new blades.
Place a small chisel in the cut plaster and gently tap the chisel with a hammer. This should loosen the plaster from the wall.
Use the pry bar to gently pry the plaster away from the wall. Continue using the pry bar until no more plaster will easily come away from the wall, and then score the plaster again with the razor knife.
Scrape the wood walls with a putty knife to remove any plaster that is still stuck to the walls. Although most of the plaster will come off in chunks, there are some bits that will remain stuck.
Sand the walls with a fine grit sandpaper to remove the grime left behind by the plaster. It is advisable to apply a coat of varnish to the walls to make them shine a bit.
Replace all the trim pieces, carefully nailing them to the wood walls with small roofing nails. Try to use the nail holes that are already in the trim. If you can't, fill the holes with wood putty and sand it smooth.