I think this post should be in the chicken section, (this is the quail section) LOL, but many of us quail keepers also keep chickens.
One of the first thing new chicken owners do their first winter is to lock the coop up tight. Don't do it. Chickens put out a lot of heat and moisture from breathing and pooping. This moisture rises to the ceiling, condenses and unless it has some place to go, like out a vent or window, it falls back down on the chickens, making them damp and can cause frost bitten combs as it freezes. Even temps in the low 30's, and not even at freezing, can freeze combs. So, unless the chickens roost right in front of a window, leave all windows and vents open so the heat can escape. As long as there is not direct wind in their faces, let the air move. They will be a ton warmer if they are dry and not damp from too much moisture.
Do they roost or are they going to sleep on bedding? Straw is the warmest type of bedding you can use. Grass hay also works well. Fluff these up so that air is trapped in the hay so that they chickens stay warm. Shavings work well to keep them warm when they snuggle deep down into it. The problem with straw or hay is that it does not absorb as much of the smell or wetness from the poop as the shavings would. I use grass hay in my coop and have never had any problems with too much stink.
