Repairing damaged curved wall

[Justanothergeordie]

We have a hallway wall with a slight curve in it which has a large vertical crack which I want to repair. I could hear it was hollow underneath so knew a lot of the plaster would have to come off. Unfortunately big sections of plaster came off down to the laths and I’m now wondering what’s the best product to repair it with?

Should I just start with PVA mixed with water, let that dry a little then use something like Multi finish or should I use Thistle Undercoat or maybe even One Coat? I have some Toupret to finish the curved part once that's all dry but any help on the plaster underneath would be appreciated.

 

[Wayners]

Can't use gypsum plaster over wood so that will need to come off.
Fit plasterboard
How big is wall? Remove plaster and laths not an option?
Small areas that need patching you can fit plasterboard then skim

 

[StephenStephen]

...or just use lime putty and sand...

 

[Justanothergeordie]

There was only a small area where the laths were showing so I used metal mesh and Thistle undercoat/bonding. I'm adding layers of Toupret over the topples scrim and it seems to be drying fine but getting the curve on the wall is proving tricky. Any tips on a good way to get the curve the same as it is above the repair, was wondering whether a cardboard template would work?

 

[opps]

There was only a small area where the laths were showing so I used metal mesh and Thistle undercoat/bonding. I'm adding layers of Toupret over the topples scrim and it seems to be drying fine but getting the curve on the wall is proving tricky. Any tips on a good way to get the curve the same as it is above the repair, was wondering whether a cardboard template would work?

Have previously used off cuts of laminate flooring to make the profile.

I then use PVA glue to affix sandpaper to long lengths of timber. I then follow the existing profile.