I'm designing my first chicken coop, capacity: 2 hens. Everything I read mentions the importance of good ventilation, as well as the importance of keeping the hens protected from drafts. These two seem to contradict each other. I was thinking of building basically a box with a slanted roof, but where the roof slants up, not covering that space with wood but with chicken wire, so the front and sides would be ventilated on top. That would allow a draft going from side to side, but not from front to back, and if the draft is too much, the hens could move away from the very top of the coop (to a lower roost?). So my first question is: when does ventilation become too much ventilation. would my coop design be okay? Next question is, in a colder climate (it gets to single digits in the winter) would the ventilation make the coop too cold in spite of say, a light bulb to warm things up. I'm raising heavy birds (1 BO and 1 RIR). I've read that they are okay in the cold. How okay? Do they need supplemental heat in the winter?