Anantharaman kp Anandan

12 mm thick// ceiling ratio is 1/3 cement / p. sand ratio. and wall 1/4 or 1/5 cement/ Psand Ratio... U may hav heard in YouTube about Low setting cement, but it has its own disadvantage too,, so go for ultratech Or Acc both are very good cement

Ceiling 1:3, Walls 1:6.

12 mm thickness inside, 15 mm thickness outside 6mm thickness ceiling 1:4 - 1:6 ratio

15 mm/12mm thick Cement mortar 1:5 or 1:6 for walls & 6mm thick 1:3 for ceiling. Ultratec/ACC/ Malabar / Ambuja /Ramco etc..