My chicks have been outside for 4 weeks now. They'll be 9 weeks old on Monday. I've been turning off the heatlamp in the morning at 7AM and back on at 8pm. They have a nice run and usually hang out outdoors until the sun goes down then I lock them in their coop and turn on the lamp. Tonight the temps are supposed to go down to the mid-30's and the light is staying off! It was only 15 degress F this day so I had the light on for them. As you can see they prefered to be outside. The Coop!