Peer-to-Peer Standards Exchange

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I'm trying to determine the wind speed for a Risk Category II structure located on Kauai, Hawaii. When I input the info into the hazard tool, the wind output indicates "NaN Vmph." What does this mean and how do we determine the wind speed? If we can't use the ASCE hazard tool, do we use the 2018 IBC / ASCE 7-16 wind maps for Hawaii?

#ASCE7

the "NaN Vmph" means that the software developed an error.  I just ran a generic site in the middle of the island, using the hazard tool and successfully obtained wind results.  I suggest you try again, if you have not done so already, and if this does not work, try shifting you site location slightly.  In general, the ASCE 7-22 wind speed maps (and underlying data in the hazards tool database) use an updated model relative to the maps in ASCE 7-16. Therefore, it is generally not appropriate to use maps contained in ASCE 7-16 with ASCE 7-22.  However, the ASCE 7-16 maps for Hawaii did use an updated model at that time, and I do not believe that model changed in 7-22.  Therefore, for the case of Kaui, it is likely ok to use the 7-16 maps, subjectd to building official approval.

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Ronald Hamburger, SE
Consulting Principal
Simpson Gumpertz & Heger
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