I know it's been asked a million times, but here goes a million and one.... I have three 10 week olds (an Australorp, an EE and a NHR) who will be going out into their new coop in the next week or so. They've been in my house up until now & temps have probably only gotten down into the high 60's in my house. We've had below freezing temps this week, so I'm not sure how bad a shock that will be for them. Suggestions, tips, words of advice?