I am building a chicken coop and have a few questions. We live in Vermont. I am building a coop that is 3w x 3l x 5h. I am wondering if I should insulate my coop? And if a chicken coop is actually measured in cubic feet? Because square footage wouldn't take in the height factor. I plan on getting 2 bantams, 2 aracaunas, 2 silver wyandotte and 2 gold wynadottes.