Fixing insulated plasterboard to solid wall

[hairgoneJohn]

Hi

I wish to fix some insulated plasterboard to a solid end wall. It is presently smooth and plastered. I want to tape and joint and so need the plasterboard to be flat.
Do I just use adhesive or are there fixings that will sink below the surface please?

 

[noseall]

Do I just use adhesive or are there fixings that will sink below the surface please?

Both. Adhesive first. Allow to go off. Then mechanically fix

 

[martygturner]

6 fixing per full sheet, i would recommend https://www.amazon.co.uk/STAIFIX-INSOFAST-GALVANISED-PLASTERBOARD-FIXING/dp/B016DMKJZO other suppliers are available. Drill a pilot hole smack in with a hammer.