Just wondering what everyone does. At what temp do you let it get down before you add a heat lamp to the coop in cold weather?
This question is for full grown chickens. And also what part of the country are you in?
I am in western PA and I have never heated my coops. Even with temperatures well below freezing everyone has fared well. I keep back up waterers and swap out fresh for frozen water as needed. Being you are in TX, you shouldn't have any problems!
Up North in Michigan. I might consider putting a heat emitter over them if the temps stayed below Minus 30 F. We don't get that cold very often, but it usually happens a couple times each winter. For sure, we'll have minus 10-20 F and the birds do just fine.
We're in northern NH. Winter cold will get to -30F a few days in winter. A few weeks of -10F lows. No heat, no insulation and no problems.
Like any livestock you need to make sure you've proper ventilation to the shelter. Dry is the key to no frost bite. Good ventilation and all you need is to add petroleum jelly to the combs to prevent frost bite there when temps hit below -15F. I didn't add any jelly last year and the only chicken with a touch of frost bite on tips of comb was the rooster.