I live in Sacramento. The record high temperature here is 115 and the record low is 18. Someday soon, when it's legal, I'm gonna get 6 standard girls of a docile breed like dorkings. They would have a coop, run, and I would let them out for supervised wandering in a gated, fenced 50' X 100' backyard. So I was wondering: do I need solid coop walls at all? If I use hardware cloth for the run fence and run a hot wire at the top to keep out racoons and cats, could I just use a solid roof with deep eaves over the coop and part of the run and make the sides of hardware cloth? I know part of the walls would have to be solid enough to support roosts and a droppings board, but could I just leave the rest open to the fresh air? How low does the temp have to go for the chickens to risk frostbite? I'd be grateful for an answer, even though I can't keep chickens now. It's only a matter of time until we Sacramentans can.