New to keeping chickens. I've been lurking here a lot but finally prompted to make a first post due to a discussion my husband and I are having. When it gets to around freezing, should I use a heat lamp or a lightbulb for a coop that is a modified shed? My concern is that with 2 chickens that they will not generate enough body heat. My husband thinks they will be cold but survive just fine. (and they might survive, but will they continue laying-- I've heard that they will decrease production if too hot) This weekend, it will be in the high 30s and low 40s at night, but I am not so concerned about them at this temp. My husband is in disbelief that a 10 degree difference (high 30s vs low 30s) would make such a difference. So will it make a difference or not?