"Air Suit" for Green Building Renovation in Hiroshima
After subconsciously reading the title as about a "hair suit" I realized this building 'renovation' just added an air layer between a double envelope: e.g. an "air suit". And what better name could there be for two new "skins" draped over a 40+ year old building. It took some more thought to figure out why it won a Holcim Foundation Sustainable Construction Award for 2005. Perhaps the confusion stemmed from a similar US technique used on apartment flats dating from the late 1950's. Garish colored glass facade elements were simply covered over (no fooling) with punched sheet metal plates held off from the original facade by 2 foot triangular brackets. Back to our subject. The winner's explanation goes like this: "Traditionally it was easy to reuse and recycle of Japanese architecture because of wood construction (sic). Now, we are facing problem of these massive heavy tough materials [for the] first time in our history. We have to find the way to handle these first generation reinforced concrete buildings..."It seems that the recycling project, which is more like a reversion to earlier traditions, involves stripping away the original concrete exterior, leaving pillars and cross beams. The removal lowers building weight sufficiently for addition of a glass and "membrane" skin, which then gets topped off with the transluscent "second skin" shown in the picture. The gap between the first and second envelopes...a kind of architectural dermis...is described as a greenhouse "buffer" in winter and an insulative layer against the heat of summer. This space contains no physical insulation per se, and the designer seems to claim energy savings with a lowered resource committment. What kind of "R Value" would a large physical gap be able to achieve? Is it a modified Trombe Wall in a new cultural context or something entirely new? Guess you have to see it to get the answers.
The author's summary explains that "...instead of heavy and thick wall, building dresses transparent and transluscent thin skin. It's remind us (sic) traditional Japanese facade made of paper and wood lattice. Flexible communication between iniside and outside will improve relation between residents and local society"
Detailed project summary is found here, as PDF download. Note: file seems to be digitally signed.
Footnote: TreeHugger strongly recomomends you take a moment to follow the top link in this post to have a look at some of the other Holcim award winners, especially the European ones. Way cool stuff with an emphasis on daylighting and dematerialization --- elements of green design we in the US have to catch up with. There's a lot more than just recycled materials and liviing roofs to tend to.