Just put a cheap thermometer in the coop which also measures humidity. I checked a few minutes ago and it says 80% humidity and it's going to drop to 20F or lower tonght. (Sun is going down now.) The chickens' door has been open all day and they have been in and out. And I have been in and out the walkthrough door. Not sure how the humidity can be so high..or, maybe it really is cheap. I have 9 birds that share a nice coop that is 8'x8'. And I just put down extra shavings. This is their first winter, as well as mine with the chickens. Am I just being a worry wart? (Which is what I tend to do with the animals.) Any thoughts?