Hi All,
I have just stripped the wallpaper from my dining room and have
discovered some problems with the plasterwork. My house is a victorian
house and the problem wall has a chimney breast and has also been damp
proofed. The damp proofing area is fine (and not damp), the plaster is
strong and smooth, but my problems are mostly with the chimney breast
and the old plaster above the damp course.
The old plaster seems to be a browny colour (as opposed to the pink of
the newer stuff over the damp course), and seems very soft and
crumbly. When removing a couple of screws from the wall, big holes
formed. I can tell that the plaster is not well attached - it crumbles
away quite easily, and I suspect quite large sections could be easily
removed.

So, what should I do? Fill the holes, and then skim the wall, or pull
off all the loose plaster and replaster the wall? How much would I
expect to pay a plasterer to patch this up and skim? The wall is about
3 metres by 2 metres (up to the picture rail which I'm not currently
planning to remove - or would I need to remove this?).
Any advice very much appreciated.

Secondly, under the wallpaper on the outside wall was a thin layer of
polystyrene. Would this have been attached to the wallpaper
originally? What is it for? Insulation maybe, or is it related to the
damp course?

Thanks
Matthew