I want to place plasterboard against some interior walls (garage conversion)
I want to batten out the walls with timber and back the timber with Damp Proof Course (DPC).
The wall I'm battening against is not level. It's not out by much though, at most 8mm.
So far I've researched into using these shims behind the timber but I'm not entirely confident in the method which I'm going to use to get the entire wall straight.
What's the suggestion? A long piece of string at 3 points which spans the wall? Use a 1M spirit level?
What about trying something like this: https://www.youtube.com/watch?v=FuCE8xaxg2s - this seems like a waste of timber though? (planing the timber down)