So, this is our current set up. The heat lamp will be removed in a few days, I'm waiting on the youngest to feather out a little more. My question is this--the window hole is closed at the moment with some plastic to prevent drafts since the weather is turning cold. The window is also right at roost level...don't know why the manufacturers thought that was a good idea. Anywho, behind the heat lamp, there's about 7 (1-inch) vent holes above roosting level covered with hardwire cloth. Does this seem like enough? We're only planning on housing the three hens in there. For winterizing, I'm going out today to get some more corrugated side panels to close off two sides of the attached run to protect from wind and side blowing rain/snow.