My chicks are ranging in age from 6 - 8 weeks now and appear to be feathered in quite nicely. They have been in the brooder with a 100W bulb that kept the temp at an even 60 degrees since I put them in at 4 - 6 weeks of age. Everyone has been quite happy and don't seem uncomfortable with the temperature. So last night I turned off the lamp completely and they stayed at about 58 degrees (the bulb apparently has been doing much) and they seemed happy to sleep in the dark for a change. They were cooing when the bulb when out and they all settled into their sleeping spots (some on the roost and some on the floor). This morning for the first time I came down to find the cage clean! Their water was free of shavings and poo and nothing had been knocked over. I think they actually got their first full night of good sleep. They were still snoozing in the same place when I came down this morning. My question is that we will be putting them into their big girl house Friday and our temps are still dipping into the mid 30's and 40's at night. I don't know what the temp in the coop is yet but I put a thermometer out there to check it at night. At this stage they seem to have enough feathers to keep warm and fluff up at night and they may cuddle up with one or two others. Do you think it is really necessary to put the 100W lamp out in the coop? It is a small 4 x 4 coop. Thanks...sorry so darn long.