I spent a night in a climbers shelter in the Andes, in very bad weather. It was maybe 50sqm with about 50 in it. No windows, one door, which hapless arrivals tended to close during the night. Bunks up to inches from the ceiling (in my case), which was slimy and dripped. Concrete walls wet from breath. Hard to move without whispered negotiations. It was one of the most unpleasant nights I have spent. Difficult to avoid panic whenever the door closed. There is a lot to be said for windows in close quarters.