Hi. My Cornish cross and production red chicks are 4 1/2 weeks old. I have had them in a pen in my basement and I have to say, my house STINKS. I setup a pen in my barn but I am concerned that it is too cold for them out there, even with the red heat lamps. The overnight lows are in the 30's-40's right now(in Connecticut) with a couple days having lows in the upper 20's. My barn is not 100% airtight, but it gets very little if any drafts through it. I do have a wood stove out there, but it would never run all night long. At what stage would these chicks be able to go into my non drafty barn under heat lamps?