Hi there, I know there are several threads about cold weather and I tried reading through some of them but didn't really see an answer to my question. What I'm wondering is this...is leaving the pop door open 24/7 (it leads into a secure, enclosed run) enough ventilation? It is getting into single digits overnight for us right now and, while I know the chickens do well in the cold, I'm still worried about them getting too cold overnight. I have several other vents around the coop that I could open but I thought if I kept those closed it might be just a bit warmer in there. I use the deep litter method also to try to help with warmth but with little ventilation will this cause more of a problem with increased condensation or possible respiratory issues? I've attached a pic of my coop, taken over the summer, so that you can see where the vents are (the vent all the way to the right is directly next to where they roost). There are no vents on the side that faces into the run, just the pop door which you can see in my profile pic. Sorry if these are silly questions, this is my first winter with a flock. Thanks for any advice.