E. i had a similar situation. i'm sure you're already using footie pajamas, with a onsie and socks underneath...that's the best i could do. i did put a blanket on my son because our house gets really cold also, but within minutes he'd kick it off anyway. 11 months should be fine to put a blanket on him, just be prepared for it not to do much good at this point. mine is two now, and insists on sleeping with two of his favorite blankets, and his stuffed giraffe, AND his "lovies" (flannel receiving blankets), and he still ends up on top of them all, or curled up on one end of the bed away from everything. good luck!