The wife finally had enough and I had to take out my hatchlings that were about 3 weeks old to the nursery. It is a port building and I have gone to GREAT lengths to get it warm especially at night. The weather her is going down to th low 20's at night. I have two heat lamps and have an electic/oil radiator type heater going full blast at night. It seems fairly warm (about 50) when I go into the building in the moring. The chicks are all gathered under the heat lamp. Some are about, but these are the ones I put in ther a few weeks ago. I have a few bigger ones in the other side and they seem to be doing fine, but they are about the same age as the ones I put in there. So my question is when can a chick REALLY regulate it's body temperature ?? I have been told it is when they feather out, but in my experience I have lost a few with this answer. I have been told that it is at about 5 weeks, yet I have lost a few with this answer. I NEVER keep chicks outside (protected) without a heat lamp of some sort and give them plenty of room to gather under it or move away from it. I have a few more chicks in the house that I absolutely REFUSED to take outside and the wife has a vested interest in these because a few are her prized black tail bantams. But, I still worry about the ones in the portable building. This is all becuase I am a hatchaholic. I have stopped for the winter and I should have known better than to hatch this late in the year, yet here I am. Thanks in advance.