When is it too cold for a chicken to not have heat? I live in the South and rarely ever have single digits. It was 30 last night. When should I leave a light burning for them? It is suppose to rain the rest of the week with temps in the 50-60 range during the day 40 at night. The fee range during the day. Their coop has 2 wood sides and 2 screen sides and a screen bottom(the screen is 1/2 in hardwire). We are way more concerned about the summer heat. We did put a tarp on the largest screen side. They never go in the coop during the day except for food and water.