Catesby Leigh has an excellent article in the WSJ today about the recent forensics work on Pei's deteriorating marble cladding at the East Wing. It seems the extraordinary craftsmanship achieved in this building - who doesn't know the story of the handprints on the famous corner - is a contributing factor to the situation. The 1/8" joint between the 3" thick marble panels hasn't been sufficient to accommodate the concrete's plastic creep and the long-term thermal cycling induced hysteresis. The forensics teams are likely to find a few other contributing factors as well.
The first studio project I taught at IIT was a re-design of the enclosure system for the Standard Oil Building (now the Aon Center) here in Chicago, which was completely re-clad in NC granite after its Carrara marble thin-cut veneer started failing in 1989. A few pieces of marble got loose, proving that large slabs of marble could indeed fly, and the resultant studies determined that thin-cut Carrara marble was particularly vulnerable to hysteresis. Our third-year design studio project set out to capitalize on the consequent "blistering" of the skin by inserting new, mostly public cross-programming within the zones opened up by the cladding's slippages. It was huge fun since working on the then-Amoco building's cosmetic probelms while the first Gulf War was being waged offered rich territory for thinking about the relationships between energy, national security, the oil industry, and architecture.
For me, Pei's building, along with Nouvel's IMA, has always represented an approach to a neo-modernism that was effectively de-railed as Koolhaas's smug and snarky take played out. Too bad. It's a great building. It's very funny to see it described as an ultra-modern building in the print article headline.