Quote: I am not Aart, but a closed waterer would be a nipple waterer. Consider trying horizontal nipples instead of vertical. The issues of frost bite and increased humidity would be greater in a smaller coop. I keep a 5 qt heated dog bowl in my coop. The waterer, no matter what style (unless it is spilling into the bedding) will not evaporate any near as much moisture into the air as the respiration from a single chicken. Not to mention the liquid exiting her other end!!!