IFC GUIDs not random

[sjors.rumping]

Hello there, 

I've been working with Revit for years now but just came across something I haven't seen before. I created a Revit file and modelled 162 elements. I exported an IFC file, but the GUIDs in IFC don't seem to be random, just the last character is different everytime. This shouldn't be a problem, but when working with another software, it doesn't recognize the difference between capital or small letters at the end. So as an example: 3XE2xHSkX09QAXEmm5Rh1z and 3XE2xHSkX09QAXEmm5Rh1Z are the same. Also see the attachment. It shouldn't look like that, right?

So the question is, can I change something in my settings so the GUIDs are randomized? I feel like it has always been randomized but suddenly not anymore. 

Hope someone can help. Thanks.

Sjors

[Rafal.Gaweda]

Hi @sjors.rumping 

According to IFC documentation small and capital letters make a difference:

https://technical.buildingsmart.org/resources/ifcimplementationguidance/ifc-guid/

[sjors.rumping]

Hi @Rafal.Gaweda 

Thanks for replying. I know that technically it makes a difference and also that Revit and Solibri recognize that difference. The problem however is that we work with SimpleBIM as well, for the interface with Excel. We use that to be able to import Excel templates and add data to the IFC file. And, SimpleBIM does not see a difference between capital or small letters and thus, when the only difference between two GUIDs is a small/capital letter, it goes wrong. 

Is there, to your knowledge, something I can do to change the GUIDs either during export from Revit or manually?

Sjors

[Rafal.Gaweda · Accepted solution]

Hi @sjors.rumping 

Manually:

- export model to IFC with option "Store the IFC GUID in an element parameter after export"

- change GUIDs in element Properties in Revit

- export model to IFC again 

[sjors.rumping]

Alright, thank you. I didn't know Revit would actually take over the GUIDs if I change them manually. That will work for now then as there are not too many elements. 

Still.. I find it funny that all GUIDs are in a sequence.. 🤔