Coop's almost done. Its approximately 5'x5' and 3' tall. It will house six chickens to start. As you can see the top is vented on the sides and in the front. I calculate about 6 sqft of venting. I'm in Greensboro, NC. Do I need to add more vents at the bottom or will this suffice? I'm worried about my girls getting hot but the other end of the spectrum is that lower vents will be more prone to letting weather in. Just looking for a little guidance. Thanks in advance.