I've seen several threads re: hoop coops when I searched the forum, but before I go jumping the gun, I want to make sure I've got it straight: Hoop coops can be permanent housing for my girls? It looks easy, inexpensive, and like it might be OK for weather in SC, especially since I saw pictures of a few hoop coops in the snow, and we get snow MAYBE once or twice a winter if we're lucky. Do the birds stay warm enough? Input, please!