Ive been using the mama heating pad method of raising my chicks since February 24th. I love the setup and it has worked wonderfully. I have noticed now that at almost a month old, my chicks arent using the heating cave anymore, but are huddling in the corner or roosting on the roost bar above the cave. The chicks brooder is in my basement which is chilly, about 50 degrees, but not as cold as the outdoor weather, below freezing. Im assuming this is normal, but I wanted to make sure. They havent fully feathered out, but have grown quite a bit.