Thank you for this article. I'm trying to design my first coop for my first flock of chickens (to come). Ventilation is one of the topics I've been confused about still. You did a good job of explaining the difference between ventilation and a draft and the types of ventilation and ways to add ventilation to a coop. Specifically, I now know how to work some specific ventilation into the coop design to be used in the summer months. I do still have a question or two about summer -- generally, what do you do for ventilation at night? My instinct is to close up the windows and other ventilation that is down low for extra safety from predators, but it seems like I may need to leave the additional ventilation open even at night. Thoughts anyone? I plan to have 4-6 hens purely for pets. I'll, of course eat their eggs, but egg production isn't my primary goal. Since they will be like part of the family (hopefully) and since I live in the country, I'm crazy worried about predators and plan to go to the greatest lengths in coop design to keep them safe. So the thought of lots of open ventilation at night frightens me. I know it should all be covered with hardware cloth, no open holes, no large holes, but is this enough? Or can I close up the ventilation not near the roof at night? I, of course, want them to be cool and comfy. Maybe I should include insulation in my coop walls? Or a fan? I swear I'd even add an AC if it kept them safe from predators. LOL I live in northwest (upstate) South Carolina. Summers get very hot. 90s. And usually a week or few days here and there in August that may hit very high 90s or slip over 100. My coop and run are going to sit off the edge of my back yard into the edge of my woods in a small clearing that is very shaded. My coop and the attached run will be about 9-10 ft tall. The run will be wood frame and hardware cloth with a shingled or metal slanted shed roof. Again, fantastic article. Before reading, I had pretty much no understanding of ventilation other than I needed it.