Best way to repair flaking wallpaper and watermarks on ceiling

If you had water damage to your ceiling and walls you may have got the looking good but the damage is still there and should have the removed from ceiling as dangerous over time and have walls dry correctly then spay with anti fungus spray then cover with thistle bond if backing is ok and reskim

You would have to strip the entire ceiling, paint out the water stain with stain block, or oil based undercoat, and then re-paper. Hope that helps :) Colin

Strip paper back till it stops pealing ... seal area with " peel stop by Zinnser" . Fill area and feather with filler . Sand then seal with " shellac based Zinnser " paint area with emulsion, allow to dry before painting whole ceiling.