I know a lot of people use wood shavings in their coops, so do I in summer, but in winter I switch over to straw, it is very warm. I have about 6" in my coop and then have a part of my run that is off the ground with a wooden floor and covered in about 8" of straw. When the chickens get up in the morning they go into the straw covered run to stay warm. I encourager them by throwing a little scratch in there.
I have part of the run that is exposed to cold winds wrapped in thick clear plastic that I bought at the fabric shop, it keeps out drafts but, because it does not go all the way around so does not trap moisture.
I have part of the run that is exposed to cold winds wrapped in thick clear plastic that I bought at the fabric shop, it keeps out drafts but, because it does not go all the way around so does not trap moisture.