That’s a big coop! Plenty of room. Beware that insulation might be a magnet for rodent intrusion (warmth in winter). Heat lamps need to be doubly secured bc you don’t want them to cause a fire. Have you considered elevating your coop 2 feet or more? Gives the chickens space snd shade underneath.I’m in missouri. I’d like for there nightcoop to be a 8ft by 20ft size coop. I’d customize it two have 2 levels of dens for each one to have there own. And there will be a fair share of heating lights in there along with there coop will be insulated to help sure there warm in the winter. During the day my chickens roam there backyard and night they in there coop