Really?...four windows, a door, and the entire ridge cap is vented. Hmmm, seems to be working just fine for my chickens. If it was too open you would probably say it was waaaaay too drafty for the winter.
I am actually building/selling coops now. This picture is of the one I delivered Saturday. It is an 8x24 which will hold quite a few chickens. I personally have a 6x14 of the same style that houses 10 chickens nicely. You can find me on Facebook at Poultry Palaces.