@Stardustrose just make sure not to make things too airtight, air circulation is absolutely essential or the ammonia builds up in the coop & it can cause respiratory problems & thus death. I leave some air moving in my main layer coop all winter. I usually close the north windows on it but leave the south ones open a little & there are vents open all year round plus the window on the people door is always open. I may even leave the chicken door open as well this year since I do have tarps all around the run. The only part that doesn't have a tarp or plastic is the door to the run.