35°51'04.9"N 139°39'16.3"E

Breeze and birdsong alike flow liquidly, languidly into the apartment through windows thrown open wide to invite the atmosphere in. In the spring and fall, they’re kept open as much as possible, closing them only when it rains heavily enough to start coming in.

In the summer, the apartment is an oven. By midday it’s usually hotter inside than out, and stays that way even after the sun has set.

In the winter, the opposite problem. Waking up on January mornings, I watch my breath form brief clouds in the air above the futon, where I consider how warm I am under the quilt and how cold it is in the room.

In the heat and in the cold, the problem has the same root: single-glazed windows and a dearth of insulation. This is common in much of Japan, especially in older buildings like ours.

There are interventions, of course. The aircon cools and warms enough to take the edge off, but the effect is fleeting, with thin walls doing little to prevent the inside air from reverting to the outside temperature in short order.

So in the summer we run the fan and cover the windows with sunshades. And in the winter, we bundle up and spend much of our time either at the kotatsu or in front of the space heater.

But in the spring and autumn? These seasons are joyfully easy, and we appreciate that nothing special must be done for comfort. In fact, the most comfortable course of all is to do nothing but let the air flow through our home unencumbered, windows open wide.