I know that vents along the top of the coop are good, and ones on the bottom can be bad, causing drafts. I have a door that is along the back of my 8 x 4 coop, that allows my chickens to go in and out of the coop 24/7, into a fully secured run. This open door is underneath one end section of the roosting board. There is a wide poop board that is underneath the roost board, that covers much of any cold air that could come up. I'm wondering, is this still too much of a possible draft? I really like the idea of having that door open all the time, in case I can't get to my chickens first thing in the morning. That way, they aren't locked up in their coop. I included pics to show what kind of ventilation I have and where the door is located. Open door under poop board: Left side top ventilation: Right side top ventilation: Although hard to see, I have ventilation that runs the lenth of the coop, about 4'' x 8' The outside view of coop door. Has a roof on it, so rain doesn't pour right in.