I have just stripped existing wallpaper in all our rooms with a steamer. There are areas on some of the walls that have lost some of the plastering, which seems to have been a botch job previously as the coulours are different i.e. red & grey. It could also have been due to the steamer?
I have also removed old skirting boards & some of the nails securing them, but this has caused chunks of plaster to brake off/away from the wall. Some of the edging on the corners have also broken off due to flaking plaster, which sounded hollow when tapped.
How would I go about preparing the base surface, before applying the "skimming cote"? How could I repair the chunks that have come off?