>>17869904
>>17870324
In the Japanese case the overhanging roof is necessary to protect the fairly fragile sliding shoji that separates the interior tatami floored part of the house from the exterior wooden porch/engawa (That also played a role in diverting water away from the interior) During severe weather they could also be protected by wooden storm shutters that functioned as impromptu walls, which the Japanese often preferred not to use because their buildings were supported by posts/beams instead of load-bearing walls.

https://en.m.wikipedia.org/wiki/Engawa
https://en.m.wikipedia.org/wiki/Amado_(architecture)
https://en.m.wikipedia.org/wiki/Shoji