It is supposed to get down in the mid-twenties here tonight. My 1-month old chicks are outside in a coop. All of the openings are covered with a blue tarp and I currently have 4 250 watt heat lamps going inside. It is 8x4x5. Surely they will be warm enough, right? My dad says that they won't freeze if they get cold but may just not gain weight for a few days but he is an ag teacher and his knowledge is related to Cornish crosses. Thoughts?