Alright boys & girls is there anything I can put on a chimney breast to stop soot stain coming through before skimming, customer had a plasterer do up stairs and he sealed the chimney before but it's still bleed through?
Belt and braces job this one soot is hygroscopic (I think that's the word) it keeps sucking up water in the atmosphere and reactivating. Just skimming will reactivate it. Maybe a hit and miss vent in the chimney if it is redundant. Salt inhibitor etc.