I have a chicken coop that a gentleman built for me for my hens and on the front side of it, he left it open with chicken wire covering it. Which is good right now but am I going to need to cover it up during the winter so they don't freeze? I was reading a book and it said that they need plenty of sunlight and also ventilation in the coop. If I cover that front side, there won't be much sunlight coming in or ventilation. But I don't' want my chickens to freeze during the winter. I am fairly new at raising chickens so I am unsure. My hens are almost 20 weeks old white rocks if that helps at all. I live in the southwestern corner of Colorado. I think the lowest I have seen the temp get is maybe 10 degrees.