Hi Brian,
If the walls do not enclose a closed space, but are placed respecting the floor height set in floor manager and enabling the Create Storey's Overlap Slabs option in the first dialog will enable the "Export" button.
Also if the walls enclose a floor slab, space and a ceiling slab, then in that case Create Storey's Overlap Slabs option need not be on for the "Export" Button to be enabled.
Thanks
Pradnya
Brian Thomas, AIA, LEED AP BD+C
GH2 Architects
Brian: Do you have a spaces model referenced? I could be wrong, but I believe the gbXML toolset requires the Spaces along with the Geometry, so you would need to have your corresponding Spaces file with Room Name so you can push the proper room to the proper Zone.
Shawn
Thanks,
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