Thanks all for your advice. Ive included some renders that I made with view along the corridor with and without the bulkhead. I don't think renderst does it justice until you actual walk through @ frame stage. I agree that ceiling height and comfort and look, depends on climate, orientation, insulation, relative proportions of other parts such as windows/doors. Because of the Melbourne climate, we have planned for double glazing, and good insulation with R2.5 batts wall, R6.0 ceiling. We have 2.4m height of windows and door around the ground floor which is btw 3 to 3.6m so I think proportion wise should be ok. In the family where it was always planned 3.6m from the start, we have a band of clerestory windows too. We have decided not to be too excessive with windows ( ie 3m and even 3.6m floor to ceiling - how grand would have that looked though! ) to minimise heat loss during winter. Energy rating for house is 7 stars so far. Thanks for giving me the pro and cons - I have some more confidence to let it stay at 3.6m throughout now.

You can have what ever ceiling height you can afford. But also think of what height windows, internal and external doors will be. What heating and cooling system you will install. What window treatments will be required for extra height windows, etc etc. Our double storey home has 2700mm ceilings throughout with 2400 doors and windows. This height is ideal. A gable ceiling in the living and dining areas, I think, has more character than a 5 metre ceiling in one room. Have 2700 ceilings throughout the remainder of home. Depends on the aesthetic you are going for, to what the design could be.

1800mm on a 2740 ceiling height is small. What height, off the floor level, are you starting your 1800mm windows? If you started them at 500mm from floor level, this would give you are nice high window. It would be the cost of the extra wall from floor level. weigh this cost against a 2057mm window. I have 2740mm ceilings and all my living windows are stacker doors at 2340mm. If you are having curtains, you could have your 1800 windows, and have the curtain drop from the cornice of the 2740 ceiling height. This would disguise the low window. But then this also would be an extra cost for the length of the curtain.

What height window and doors are you proposing. If 3 metre ceilings then 2400 doors and windows would look better. This will then add extra cost for window treatments. Also in the kitchen, with a 3 metre ceiling, where would you stop your overhead cabinets, would you have them to the ceiling? Or standard height? I personally would do your pitched ceiling in living area, and 2700mm everywhere else. This will add extra interest with the change of ceiling height. 2700mm are a good height.