Ashrae 90.1 - Unmet hours

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Ashrae 90.1 (2004) Appendix G3.1.2.2 requires a baseline building to
have less than 300 unmet hours. What exactly does this mean?

To illustrate my question: assume you have a building with 301 zones,
and each zone has 1 unmet hour per year. This gives you a total of 301
unmet hours, and requires you to increase your baseline equipment
capacity. But you could argue that, on average, the building has only 1
unmet hour per year.

Have any of you run into this? Is it addressed in an addendum
somewhere, etc?

Any help is appreciated. Thanks,

Jim Crockett, P.E.

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