I'm confused by the instructions for how much ventilation a coop needs! They seemed plenty happy in the summer, but it's going to be between 5 and 25 degrees F for a week! I have sand in the bottom and their droppings were frozen solid last night. I'll close the door at night to keep them warm, it's rather large, but do I need more ventilation? Less? I have eleven chickens in there right now on. Two roosts. More than enough room on them. I will cover the top vent when we have windstorms, it can get pretty bad. Here are a couple of pictures of my hen house. Please let me know what you think! The run now has a peaked roof and the roof and far side are covered with vinyl signage.