I just got some pullets from Cackle Hatchery. Really like that place. Welsummers, and BC Marans, (my usuals) plus some Barnvelders, which I've always wanted to try out. I've brooded lots of chicks, but generally in the spring, with a lamp, etc. A few times I've hatched some in the summer, then brooded them with no trouble in a garage or barn during hot 90+ weather with no lamp, except at night if its going to cool down. I was looking over the Cackle instructions, and it mentioned to always keep the chicks in a climate controlled room, and under a lamp. I'm guessing they are assuming it is rare to have conditions outdoors suitable to brooding chicks. We're going to be right around 100 degrees the next who knows how long. Overnight lows just under 80. My plan was to keep them in my attached garage the first several days, then move to larger brooder in barn. (how I've always done it in summer) I'll probably put a low watt lamp on a corner overnight. Still it will stay about 85 in that garage. Right now they are in a perfect "formation" that looks not too warm, not to cool. Just curious what the sentiments are. Never had an issue before.