Something that hasn't changed since Mies' day: So much glass creates an unusually high heating and cooling load.

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Mulpuri says the premium his company will charge for the glass should be offset by the savings in heating and cooling systems.

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Lest you get carried away with the thought, though, note that there are simpler kinds of glass--coated glass, that is--that also save on heating or cooling bills.

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Etchingham could see that the glass table in the hotel suite was smashed and that Hendrix had the heating on full blast even though it was a warm day.

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