NO METAL ROOFING! Build a portable coop/pen that is easy to maintain and great for your chickens. A-Frame Designs provide very small space for your birds, give them more roosting room. Metal roofs get overheated in summer and freeze, causing interior condensation during winter. Portable Coops in my opinion should NOT be used for year round chicken housing... in winter, they do not have adequate forage and the space is too small, a portable coop should be a summer temporary residence. I suggest also having a coop structure with adequate interior space (4 sq ft per large standard chicken).. thanks for caring about chickens!