Ok so I've read all different posts on here on if I should use a heat lamp or not. My coop is uninsulated but is draft free when I close it up at night. Do I need a heat lamp? My husband says we do, does not want them to get cold at night. My chickens are all hens and are about 17-18 weeks old. Uggh I'm so confused on what to do. I went and bought a heat lamp, it's 250 watts and gets pretty warm. It will be about 40 degrees tonight. Should I use it or not? Please help!