QUOTE(cheon @ Jul 23 2013, 12:16 PM)
I am an owner of Type A too. Can i have your opinion?
Is it worth that i cover the whole second floor? This will make the house a lot bigger~

Well as Malaysian Driver said, you can but you will do away will the existing concept.
Just a few concerns I guess. The ground floor ventilation will still be there but reduced. The air flow will be through your staircase area.
Of course lighting will be another area you may need to look at. Your house is essentially 3 floors. So the ground floor may be dark. I am not sure, can't tell about how bright it will still be after covering.
You should check on whether it is necessary to reinforce the foundation although it is unlikely that you will actually need to by adding the floor space.
The other part is on the approvals part. As you know we are still under master title and we be applying for strata in future. Not sure whether management would easily allow this type of modification at this point of time. You will have to check with them.
And I am guessing you would like to build that portion into a room right? You will have to get bomba approval later on also if you want to do it officially.