I played with adding insulation to our coop to see if it would improve the feed to egg ratio during the winter. immediately the chickens would contort into any necessary position to get at any insulation that wasn't covered up, I had to cover every bit of it up or they would go at it with great persistence. it hasn't seemed to help that much. my conclusion is that ventilation, wind break and light are the three major keys to health and egg laying production. in the winter I use a 60W equivalent or greater LED bulb to keep them laying. they still stop to molt, but then get right back to laying. I have it on a timer to start a bit early while it's still dark, and to go a bit into the night. seems like 13-14 hours of total light per day is adequate to keep them laying while giving them plenty of rest. int he summertime, we get long days so there is no need for supplemental light.