how about upgrading the 3-blade fan to 5-blade fan?its cheaper,and i believe 5-blade fan give more cooling air.

sounds high tech water to vaporized ehehhe

the fan will still blow the same room punya "Warm" air around.. = no diff

we need to exhaust the warm/hot air out.. or prevent more heat/warmed from building up

= insulation or exhaust or aircond

Exhaust fan is supposed to create  air flow through the building (convection) i.e. to improve ventilation.
It doesn't help to block off the heat from radiation.
To reduce heat from radiation, you need a medium to reflect heat from a building - a reflective roof (not applicable to houses) or reflective aluminium foil.  It works on the same principle as the thermo flask.

I hv nippon solareflect. Not convincing,

Thinking of aluminium cladding on externall wall facing sun like Paradigm Mall

I think some1 made a thread similar to this topic. It really depends on where the sun fall during the 'golden hour'. If your room is facing the west side, you will definitely get a free sauna from the sun. Like my old room, I got it straight hitting to my room and it's really a hell where the heat will stay until the next day. I had blind outside of the window, with my window being tinted, and curtain as well, but it still wont help. Even if I on my aircon for the whole day also it's the same