I would rather have a slighty cold room than a hot one for my DS. He is in the coldest room too in our house. There is a centrak heating radiator in the room, but I turn it off at the wall, about a hour before he goes to bed as it gets way too hot. The residual heat seems to linger for a while, as when we go to bed (3/4 hours later)the room is still warmish.
Last night was COLD, his room was hovering 15-16, but when I felt him he was toasty.
Heres what we have done.
Thermal lined the curtian over his window and placed a draft excluder over the sill.
On a very cold night he wears-
He wears a l/s vest, baby grow and down filled sleeping bag. If very cold- big socks too, and then when we go to bed, I check him and if he feels cold, then a thin waffel blanket on top.
So far this has been fine, and he will be 2 in December went into his own room at 7m.
Am loving the idea of arm warmers though!