[masklinn]

Bangkok being tropical, in summer the sun basically shines straight down (and some on the east and west walls in summer and winter), some N/S roof overhang and you’re set. In Northern Africa and southern Europe the sun is significantly lower and will shine straight through windows.

There’s definitely a cultural or historical component. In my experience shutters are extremely common, near universal, in southern Europe but much less so in northern. Which is a shame because a modern PVC roller shutter, well installed and with insulated slats, also does wonders in winter.