Painting over wall paper? And chimneys walls

[JP_]

As a short-term measure, is it OK to paint over wallpaper? Will possibly eventually put insulation backed plaster board up, and skim, paint etc. Or just strip and paint if the external insulation is sufficient.

Also, I assume that the chimney is going to be solid brick all behind the paper? Will have to pop the tele on the wall, so above the fireplace will have to do for now....

 

[footprints]

Yes, but you will need a stain blocker to kill the dark colours and also a special primer if the paper is vinyl so it gets proper adhesion.
I would suggest two coats of Zinsser bullseye 123 it will do both jobs, then overcoat with your paint of choice.

Chimney would normally be one brick thick on the face, have a look up the chimney if it is a normal size (roughly a 9 inches to a foot square) chances are it is brick, if it is smaller about 9" x 4" it is pre-cast and anything is possible.