I am building my first coop which will be 7 feet by 8 feet. Do I need to install vents? And if so do I place them on the north and south sides or the east and west sides? Thanks for any info you may be able to provide. I am not sure of my predator situation, the area around the coop will be fenced but I do not know if I will be closing up the coop at night to protect the hens.