Our birds are all fully feathered I asked the same question the other day and was told they will be fine. I have hopefully made our coop draft free but it still has plenty of ventilation. I am still concerned about our 6 Silkies but I will not be using any heat at this time. I'm hoping they will generate enough heat on their own.Anything I should worry about with this cold weather front coming through as far as my birds are concerned? In Statesboro. Coop is pretty locked down with nothing but the door open at this point.