Home DIY

https://www.solvite.co.uk/en/products/repair/wallpaper-repair-adhesive.html

currently making some headway with this - wet the area, peel it back a bit, squirt this in - so far so good but we've not painted yet

See my post and subsequent comments on this page: https://www.lfgss.com/conversations/178667/?offset=16625#comment14595189

What I ended up doing was:

1. No Nonsense super glue under all the raised bits, then press down. Use a small pin or needle to hold down if fingers aren't practical in that spot.
   
2. super glue over the top of the join to seal. This will leave a raised section to be sanded back.
   
3. once dry and hard repeat 1. and 2. where necessary / if bits have lifted
   
4. sand back
   
5. light fill with polyfiller from a tube where necessary
   
6. touch up with base coat paint
   
7. paint
   
   

I had to do 3 x 2m sections of varying shittness above a rad. I would rate success level at 85%, due to some visible lines from where I gave up on steps 4. and 5 and some where I thought it looked alright so didn't intervene. None of it has lifted.

Your area looks pretty big and in a shit location to work, so I would strongly consider whether you have the budget to have it reskimmed.

However, I do get that you are on a budget so maybe go with wallpaper paste in small sections/steps first. If that doesn't work try my method or the other peoples suggestions in the posts I linked.

I think you already have most of the answer but there are some additional bits that might help.

Border paste, it's a kind of ready mixed wallpaper adhesive, bit stronger than the usual.
Syringe, you can get a big one for decorating. Use it to squirt wallpaper paste under those edges.
Decorators sponge and clean water in a bucket. Use the sponge to smooth out the paper and make sure you wash all the excess paste off otherwise you might have trouble painting it.

Small gaps and damage can be filled with something like Toupret TX110 if you really need to. There's also a tape made by Tesa called crack cover which can be useful in these cases but is not a necessity.

If you are super careful you can get away with decorating afterwards and have it look half decent. Usually needs a couple of coats of paint though, best to use something with a lot of solids in like a specific ceiling paint or high cover paint.