I'm from the La Crosse area and my flock consists of only silkies. This past winter was my first and, as you know, it was brutal. All of my silkies survived. I only added heat when it got to 20-30 below zero. From what I've heard from other silkie owners, I probably didn't need to give them heat, but it made me feel better. Just make sure the coop is dry (get a hygrometer), draft free, and properly ventilated. I don't recommend insulating because it holds moisture in, and too much moisture and not enough ventilation was my #1 biggest problem. I had all sorts of respiratory issues in the winter so I added more vents and hopefully that's not a problem this coming winter.