Zones export to IFC takes 4 hours

[Erick Thomas]

Hi everyone,

At the office we are exporting a project to ifc format.
When we exported the project with zones included it took aprox 4 hours to be finished and without the zones it took 1-2 minutes.
The sizes of both IFCs didn't differ that much: 38mb for the first one with zones, 34mb for the second one.

We have created custom information for te zones in the property manager but I'm not sure this is causing the problem.

Does someone know what could cause the enourmous increase in time when exporting to IFC with zones?

Thanks in advance!

[Laszlo Nagy]

You can test if the Zone Properties cause this:
Export all your Properties into an XML file so you can import them back later.
Then, delete all your Zone-specific Properties, and try to export the IFC again.
If the export takes little time, then the Zone-specific Properties are causing the export time increase.

You could also check IFC Translator settings, specifically, Data Conversion settings. The IFC Translator you are using may export a lot of types of parameters and properties that are not really necessary. Uncheck any checkbox you do not need, and see if that helps.

[Erick Thomas]

Thanks for your help. I've removed all of the zone properties (without importing them back) and it didn't work.

I copy/paste the zones (with their properties) in a fresh new file and the ifc export worked. Maybe this means that the zones properties are not the problem? I can't copy/paste the whole project in a brand new file because we have a lot of information in the existing one (layouts, transmittals, etc).

[Laszlo Nagy]

I would look at the difference between the two IFC Exports, specifically the differences in settings of the IFC Translators used. Then you will hopefully be able to find the setting that causes the swelling in file size. It may take some testing to do though.

[martinij]

In my experience the export takes forever when "IFC Space Containment" and "IFC Space Boundaries" are on under "Data conversion settings". 

It's to bad, because I think the relasjon to spaces are one of the most beautiful aspects of IFC.