I wore thin trackies and tshirts with mine. I can say that Selangor may feel cold when walking around viewing the rooms and stuff, but my rooms that I was in for both DS and DD1 were really warm, and sitting in bed in light trackies and tshirt (short sleeve) was enough. I slept in pj bottoms and a singlet top and was fine with just the sheet over me as well.

Oh, and DS was a summer baby and DD1 was a winter baby - wore the same clothes for both.