On 03/07/2019 00:27, Al wrote:

Hi,

During the warmer humid weather we get during the summer months, I find
the embossed ceiling paper in the lounge and bedrooms tends to sag a bit
in places. It won't be much longer before a strip comes off altogether.
The easiest way to fix this would be to tease the loose ends away and
downwards, then paste the *ceiling* and use a brush to press the paper
back in position. It would be much better to do this before it peels away
completely as I'll never get it precisely in the right place again. It
was done by a pro 7 years ago and I don't have that skill.
Will the method above (pasting the ceiling instead of the paper) work OK
or is there some issue I've overlooked here?

TIA

Years ago I had a little tube of "glue" that was intended to stick down
loose edges and corners of wallpaper, e.g. in window reveals, doorways,
etc. It was just PVA diluted to "yoghourt" consistency and worked very
well even on painted paper.

Not sure if your problem is caused by moisture or perhaps by loosening
of a friable surface, but I think I'd go for PVA rather than traditional
paste in your case too.