Hi, I've got a window that I prop open on the side of my coop, but when it's shut it's not air tight - it would let little drafts in, I'm sure. Could I just take off the window or prop it up and cover the opening with sturdy plastic for the winter? Or maybe screw on some plexiglass? I've another window on the other side that would need similar treatment. I want to keep drafts out but let in some light for my girls. Here's a pic - you can see what I mean. It's the window above the nest boxes. Someone didn't close it fully, but you can see the cracks all around it. Just looking for suggestions here. Thanks! We're in Idaho, by the way - it can get down into single digits at night in winter.