My three young Silkies are experiencing their first taste of real cold. It got down to one below zero F last night and is a toasty 18F today. Their coop is well built, but not insulated or heated. They have heated water. Today I attached a few horse grain bags on the West facing side of the pen where they like to hang out to cut down on the wind. They always have access to layer crumbles, but I've been throwing out at least a cup and a half of scratch for them for extra warmth. Do I need to worry about giving them too much scratch since it is not their only source of food? The hens are young, but are still laying every 3-4 days. I had plans to turn a former rabbit hutch into a protected winter run for them, but now it's frozen to the ground and probably won't be moved for a while. They hop out onto the hay covered snow happily in the morning. Am I exposing them to too much cold weather? They are always free to go into the coop. They seem happy, but I don't want to go out some morning to find Silkiesicles. These are my first chickens, and I live in New Hampshire. Thanks!