Earthquakes and ungreen housing trends in Japan

Why do the Japanese bulldoze houses after only 30 years?  Contrast this approach to the built environment to the European mindset of maintaining and renovating buildings for hundreds of years.  What gives?

In this Freakonomics podcast, the economist Steves dissect this phenomenon, citing local experts and (of course) statistics.  For example...

Japan has 3.8 times more architects per capita than the USA, and 2.1 times as many construction jobs.

Half of houses are demolished within 38 years, compared to 100 years in the USA.

Why?

Theories range from spirituality to post-WWII history to earthquake building code revisions.

As a structural engineer, that last part caught my attention.  Did you know that 20% of the world's earthquakes of magnitude greater than or equal to 6 have occurred in Japan?  In the years since WWII, this has resulted in Japanese building codes' earthquake provisions being updated at a greater frequency than in most countries.  Homebuilders there use this as a marketing device to encourage consumers to rebuild rather than renovate... and this has contributed to a culture of Do-It-For-Me more than DIY.

In addition to being environmentally unfriendly, more than one economist has suggested that this custom may be contributing to the economic slump in Japan.

Listen to the full podcast here:
http://www.wnyc.org/story/why-are-japanese-homes-disposable/http://www.wnyc.org/story/why-are-japanese-homes-disposable/

Image credit:  http://www.busyboo.com/2008/08/25/japanese-house-design-mineral/