Can you open Revit 2016 (or 2017) and click on the “Sample Architecture Project”
Export to IFC type IFC 2x3, no split, no space… save to MODEL1.ifc… then… re-save to MODEL2.ifc
Same model… saved twice on two different names.
When I compare MODEL1 to MODEL2 (in this case, with Solibri... NavisWork will give same result), 2 Curtain wall will be identified as Removed/Added
Analyse...
"Looks like it is an issue with the Revit IFC Exporter and Curtain walls. I reproduced it. The issue is that the GUIDs are changing across exports for these curtain walls. You can see in the first export, the GUID is: 2elOmkYdT3qPFUzmTp$dw8. If you export again without changing anything, the GUID is changed to 0UUtcatr578O0u7_VS3Yak. Notice that the BAT, which is the Element ID has not changed. Therefore, it is the same element, not removed or added, but SMC uses the GUID to determine if it is the same element."
How come?
If you would like to refer to this comment somewhere else in this project, copy and paste the following link:
I can see it happening for element 707722, which is a curtain wall on the Northeast side of the house. Why that one is different and the others are the same, I can't see. I'll file an item for Angel to investigate.
If you would like to refer to this comment somewhere else in this project, copy and paste the following link:
Hello, any update on this yet?
We have quite a lot of Curtain walls in our project that changes GUID all the time. It makes <Model Comparison=""> in Solibri very noisy.
If you would like to refer to this comment somewhere else in this project, copy and paste the following link:
For the specific case above, windows that span two walls are represented differently in IFC and Revit, and the "second" opening in IFC currently gets a "random" GUID. We can try to stabilise that GUID.
If you would like to refer to this comment somewhere else in this project, copy and paste the following link:
Simple to reproduce....
Can you open Revit 2016 (or 2017) and click on the “Sample Architecture Project”
Export to IFC type IFC 2x3, no split, no space… save to MODEL1.ifc… then… re-save to MODEL2.ifc
Same model… saved twice on two different names.
When I compare MODEL1 to MODEL2 (in this case, with Solibri... NavisWork will give same result), 2 Curtain wall will be identified as Removed/Added
Analyse...
"Looks like it is an issue with the Revit IFC Exporter and Curtain walls. I reproduced it. The issue is that the GUIDs are changing across exports for these curtain walls. You can see in the first export, the GUID is: 2elOmkYdT3qPFUzmTp$dw8. If you export again without changing anything, the GUID is changed to 0UUtcatr578O0u7_VS3Yak. Notice that the BAT, which is the Element ID has not changed. Therefore, it is the same element, not removed or added, but SMC uses the GUID to determine if it is the same element."
How come?
Good question! We'll take a look.
I can see it happening for element 707722, which is a curtain wall on the Northeast side of the house. Why that one is different and the others are the same, I can't see. I'll file an item for Angel to investigate.
I also have this problem but with a Window/Door.
Want to help change the problem but how can i replace the existing installation by my own build?
Hello, any update on this yet?
We have quite a lot of Curtain walls in our project that changes GUID all the time. It makes <Model Comparison=""> in Solibri very noisy.
We also see this problem. I our case it is Windows spanning insert over two walls, that varies GUID value. See the attached IFC, rvt and image.
For the specific case above, windows that span two walls are represented differently in IFC and Revit, and the "second" opening in IFC currently gets a "random" GUID. We can try to stabilise that GUID.
This is needed, when using tools to tracks issues (BCF) and you want the Guid to track the element and issue it gets lost after a new export.