First time chicken owner....We just purchased chicks 2 weeks ago, chicken coop is almost done and we are trying to decide what to use in coop and run. I definitely want to use sand in the run, but should I do sand in the coop as well? I worry that in the winter time the sand would be so cold (live in PA outside of Philly). Does this present a problem with anyone else? I have read so many threads and I have never read anyone else concerned about using sand in the winter time. Sorry if this seems like a dumb question... I am assuming for the nest boxes should I use straw or pine shavings?