IFC validation error

[GVladislavG]

Hello, xBim team!
I got this validation error
IfcBuilding '{label}' has null IIfcSite (invalid parent){} while analizing IFC file, created with xBim.
But BimVision shows project hierarchy correctly. Building is attached to IfcSite.
What is the reason of this problem?

Thanks!

[martin1cerny]

Where is this validation error coming from?

[GVladislavG]

It's comming from one of viewers, that makes this validation and refuse to process IFC-file.
IfcBuilding.IfcSite is readonly property and I couldn't find the way to set it.

[martin1cerny]

Do you use IfcRelAggregates as shown in the documentation?
https://standards.buildingsmart.org/IFC/RELEASE/IFC4/ADD2_TC1/HTML/link/ifcspatialstructureelement.htm

[GVladislavG]

Yes, I do. I tried two ways
ifcSite?.IsDecomposedBy.FirstOrDefault().RelatedObjects.Add(building);
and
ifcSite?.AddBuilding(building);
And both doesn't set buiding.Site property...
Result IFC-file is attached
test.zip

[martin1cerny]

Have you checked the actual IFC file you have created? Does it contain the aggregation relation?

[GVladislavG]

How can I check it?

[martin1cerny]

Just open the IFC file in text editor and check if there is IfcRelAggregates object connecting the site and the building.

[GVladislavG]

Yes, result IFC (in test.zip) contains aggregation relation. IfcRelAggregates object is connecting the site and the building and also
the storey and IfcBuildingElementProxy

[martin1cerny]

In that case, you will probably need to raise the question on the other side - with the developers of the application complaining about the missing 'property'.