When we moved into our new home, it came complete with four hens in a tiny coop with a tiny run. They slept on the roof. Since then, we built them a 5-by-8-foot, raised barn/coop and started over from scratch (no pun intended!). Next, we constructed a 10-by-16-foot run with an angled roof with corrugated plexiglass for water and snow runoff. In the winter, we put corrugated plexiglass around almost the entire run to keep it nice and warm. We added an adjunct 10-by-12-foot run with a slanted shingled roof so they could also see out and have fresh air, and connected the two with a chicken door. We currently have young pullets, so a screen blocks the two sides and a mini-coop/loft sits in the young ones’ run.