My wife and I recently converted and old dog house into a chicken coop. I am a little worried about the ventilation and the sizing of the entry door. We live in Wichita Ks so it does get chili in the winter time but very rarely below zero. I am not really worried about the winter the summer (is what worries me I am afraid that they will cook in there. They will be pretty much free range because we will allow them to have the entire back yard durring the day. We are thinking about getting 5-7 orpingtons and the coop itself is about 15sq. It has a second floor for the nesting box. We put two floor registers one on each side of the house and the overhang of the roof is not sealed. 1. my question is should I be worried about them in the summer at night when they are all in the coop? 2. What size should I make the entry/exit door for the ladies?