You can try it as planned and then keep an eye on temperatures inside vs out and make adjustments if necessary later on.That would give me 6.68-7.18 square feet of ventilation for 5 hens (over 8.5 square feet with the main door open). What do you think? Would that be enough? Over half of the coop will be in the shade all the time, but because of our heat, do I need to squeeze out more ventilation?