Andrew Gabriel wrote:
You can apparently plaster onto glass if you PVA it in this way
first.

Well, THAT sounds promising! If putting PVA on glass will let the glass
take plaster . . . it'll surely take heavy paper.

I share the views of others on safety. Might be better to stick
sheets of hardboard on first, but even then it may be an
unwelcome surprise for anyone who later decides to pull down
what you've built.

There won't be a safety problem as long as I am the owner of the house,
and of course I'll win the next owner when the day comes we decide to
move on. Probably tell people when showing them round that there's nice
mirrors beneath the leather-looking panels if they're interested.

Eddy.