I read that post, it was interesting to know how some would over heat a coop. But like I said I only switched to a 100 watt bulb this morning to help keep the water from freezing, it is only above the water. We have been trying to find a water dish that is heated and our town doesn't seem to keep them in stock. The coop is naturally warmer than outside, not from the little lamp I put in there. We put foam insulation on the walls under the wood panels to help keep the coop warmer than outside. Central Texas normally doesn't get below 20degrees in the winter, but this year has been way more different.
There have been accidents all over the metroplex and schools closed all day and even tomorrow, not a snow day they are calling it an ice/freeze day. Texans weren't taught to drive in snow/ice conditions like the northern states were. I learned to drive in PA and on 3" thick ice so I knew how to handle a slide. But we never owned chickens there and had no clue what temps they could handle. I'm confident they will be ok through this next week, as long as I keep their water from freezing.