Because the walls are 2750 high we will be using 1350 gyprock.
The question is - will the last 50 mm gap be adequately covered by the cornice.
I bought a sample piece from Bunnings and installed it against the wall and ceiling in the dining area.
Looks like 75 mm cornice will do the job.
I will fill in the small gap at the top but the main issue is that I will not need to flush it.