This is my first winter having chickens, My coop is insulated and has two windows, one window, we covered with plexi glass (which can be taken off in summer) and it has a shutter. The other one has a shutter, but no plexi glass, for ventilation. we have a roof vent also. The window with the plexi glass has condensation on it. Is it due to their breathing? The pic on left is the one that is now covered with plexi glass. The one on the right has a shutter that comes down. Do I have enough ventilation?