If you are considering ducted air conditioning and wonder if the equipment will fit in your roof space (the space between your ceiling and your roof) then here are a 2 simple checks:
The air return filter on a ducted air conditioning system requires regular cleaning.
Modern construction methods and suspended T-bar ceilings leave little room for ducted air conditioning systems. However they can be installed using slimline ducted systems. There are a number of manufacturers that supply slimline ducted systems e.g. Mitsubishi Electric, Daikin.
Diffusers are room air outlets i.e. what you see on the ceiling when there is a ducted air conditioner installed. There is a range of air supply diffusers to suit your design (size is important) and taste.The size of the diffuser is principally determined by the air flow. Architecturally in most cases it is more atheistically pleasing to have 2 smaller diffusers than one large one.