If you encounter wallpaper that s been painted over first try the wallpaper stripping.
Hanging wallpaper on plaster walls.
Sizing is a compound of chemicals that acts as a buffer between the wallpaper backing and the plaster surface.
For speed even application i use a roller.
Plaster walls have a tendency to crack and crumble if you attempt to hammer a nail directly into the wall.
How to wallpaper or paint directly on plaster 1.
Firstly make sure plaster is fully dry 7 10 days depending on drying conditions.
Step 1strip off the outer face of the wallpaper leaving only the backing material and glue.
Remove as much furniture as possible from the room.
Prepping plaster walls for paint wallpaper painted over wallpaper.
Best o luck paul.
Although this may sound like a measurement process it actually refers to treating plaster walls with a product that allows the paper to stick better but not so tightly that you can never remove it.
Take down pictures mirrors or anything that s leaning or hanging against your walls.
Place any large pieces of furniture such as sofas in the center.
Place these in another room.
Pull out all remaining plaster and lath and re build the walls with drywall or to be historically accurate plaster and lath.
In most cases of multiple wallpaper build up though the plaster will be a lost cause.
Adhesive picture hooks are the best way to prevent damage when hanging a picture but pre drilling the hole will usually prevent cracks and chips from forming as well.