I'm posting a picture of my coop in progress. Keep in mind i live in Wisconsin. We have cold winters here. So, the bottom is completely fenced in with hardware cloth, there will be a ramp to go up in the coop from underneath. Now what I'm wondering is... at night, can the access door from the bottom part up into the coop stay open at night or does it need to be closed. I'd like to build a larger run for them as an addition to what we have now and let them out there in the day, but was thinking at night they would be confined to what you see in the picture now. Also, my baby chicks are 5 weeks old, its been getting cold at night enough for frost. I have them in their makeshift brooder bin in the garage, a small amount of heat lamps on them (just b.c its gotten so cold at night). Are they ok to move into the coop with a heat lamp at this point? I've read that at 12 weeks they can withstand any weather but anything younger than that they need to be at 60 degrees. They are outgrowing the space I have for them now and i'd really like to get them in the coop. Any suggestions would be wonderful!! Thank you!