I think there's a bit of broken telephone here. A few specific buildings, like the Ise Grand Shrine, are rebuilt every couple decades as a cultural practice (or

I think there's a bit of broken telephone here. A few specific buildings, like the Ise Grand Shrine, are rebuilt every couple decades as a cultural practice (or imperial edict) specific to those sites. It definitely does help maintain active practice of traditional construction techniques. Others, like the Nara Todaiji temple, are very old structures and preserved as best as possible, being repaired and rebuilt only when necessary eg. due to fire or structural damage. The practice of frequently renovating or rebuilding residential houses is quite unrelated, and more of a postwar trend.