Hi all, New to the forum as I am new to raising Chickens. I have 4 hens (2 Rhode Islands, 1 Barred Rock, and 1 Golden Sex Link). They are about 9-10 weeks old. I moved them into the coop about a month ago which is 4x4x4 for the house and sits up about 40" from the ground and is uninsulated plywood construction. Since I moved them in there, I have had a heat lamp running all the time in fear they will get too cold. I live in the Portland, OR area and the lows have hit the high 30s to high 40s for the overall low. 1) When do I stop worrying about the use of the heat lamp? 2) Is there a temp sensor product out there that will turn on the heat lamp after a certain temperature is crossed? 3) What temperature should I turn on the Heat lamp?