Oh, and as to coop mess, i used to use shavings, and the poop would make this giant frozen teepee on top of the shavings.
Even with no water in the coop, the shavings would freeze together into a giant block. I have high humidity since i am on the coast.
Anyway, this summer I installed poop trays under all of my perches. I think that they are close to miraculous, that is how good they are, and how much cleaner the coop stays. Wow!
I am hoping that the poop trays will = a much cleaner and easier to keep clean coop (i don't think the PDZ will freeze into a solid clump) and the poop trays do greatly increase the square footage of my coop.
Large square footage is vital in the winter to help cut down on cannibalism and related nasties.