The interior of Christ the Light Cathedral doesn't look like the exterior, so I thought there must be some mistake in the images. But looking into it further, I found the explanation: The exterior/interior walls are made up of four walls, an aluminum curtain wall, a steel framework supporting a glue-lam rib wall, which holds up the array of wood beams that look like louver slats all around the interior:
When you multiply the walls by four, that makes the high cost more understandable.
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This is not a simple concept. Why have four walls instead of one wall? Most buildings have just one wall for keeping the wind and rain out. The expense and maintenance concerns of four walls instead of one must have been a hot topic of debate.
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The reason (it seems to me) that they chose four walls was that they wanted this effect with light on the inside of the building, and to get it, they had to have this array of slanted beams looking like louvers, which you see inside the cathedral, all around on the walls. But to have that, you need a ribwork of glue-laminated columns to hold them up. But to have that, you need a grid of iron bars with kickers to stabilize the columns. But that's going to look terrible on the outside, so cover it all up with a low-budget curtain wall, like they do on all the high-rise skyscrapers these days, and while you're at it, make the iron gridwork a little stronger to support and brace the flimsy curtain wall, and everyone's happy.
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Okay, 9 years later and nobody's happy. Oh, well. At least they got some awards for a while.
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