On heat in buildings. Central heating is not common in residential housing in Japan. When I lived in the far north, I would turn off my kerosene heater at night, climb into my futon, pull on my stocking cap, and sleep (winter, obviously). When I woke up, I’d reach over to turn on the heater and wait for the room to warm. I had to keep my contact lens container near, because when I left it in the bathroom the solution would freeze overnight.