Skimming walls that have patches of paper on them...

by SamCF
(Kent, England)

Hi, we are due to get our bedroom completely skimmed over, but have found as it's an old 1930's house, the layers of wallpaper are very stubborn to remove!
We have got the majority off with a steamer, but have some patches that we can't seem to shift. Can the plasterer skim over this, or do we need to remove it all? Would a PVA mix painted over walls prior to skimming be needed too?
Thank you for your help.

Answer
Hi, Every effort needs to be made to remove the paper - otherwise when the plaster is being trowelled and finished in the final stages - the paper then (after being enclosed in wet plaster for over an hour) often peels off to leave a mess of the finished wall. It is therefore worth trying as hard as you can to remove paper. I guess you've already tried scoring the surface to let the steam penetrate further.
The only time I have managed to successfully plaster over wall paper was when the paper had been painted with an oil based paint and no amount of moisture was going to penetrate. However this is very rare and I know it's painful but try with extra steam or water to really soak into that paper for removal.
The walls will need preparing with PVA but unless you have specific instructions from the plasterer it is best to leave this to him - as this will also control the suction.

Paul