Polystyrene and drylining

To straightened and tidy up a wall I’m going to dry line it with 2 x 1 battens and screw fix plasterboard before getting it skimmed. Any advantage to fix 1” polystyrene sheets between the plasterboard and original wall to increase insulation?

Regards,

Not a great deal, but then, it doesn't cost a great deal either. You pays your money and takes your choice. A small extra cost for a small amount of extra insulation. If it's quite a cold room, it could be worthwhile.

Too late to be interest to you, but perhaps my experience is of interest to others with a similar dilemma. I recently dry lined our bathroom which juts out at the back of the house and so has 3 external walls. The walls are solid (1930's). Whilst it was never a particularly cold room the benefit of using insulated boards was immediately apparent - certainly warmer but perhaps most valuably in a bathroom, much less condensation. I'd recommend insulated boards every time.