Hi ​@charry ,

According to CityGML 2.0 format specification and XML schema, for BuildingInstallation, the valid lod name is "lodl2-4]Geometry" and the valid feature role is "outerBuildingInstallation". Also, BuildingInstallation features should be children of a Building feature. See also this document in the FME CityGML Reader/Writer Help to learn more about avaliable lod name and feature role for each feature type.

Writing CityGML from FME

I'm not familiar with KITModel Viewer, but guessing that it would parse the XML schema strictly when reading a CityGML dataset.

If you are attempting to create a CityGML dataset describing only BuildingInstallation features, try:

• Change lod name and feature role to valid values.
• Add "gml_parent_id" representing "gml_id" of parent Building feature to every BuildingInstallation feature.
• Write Building feature(s) having "gml_id" (= "gml_parent_id" of children BuildingInstallation features).

This screenshot illustrates a minimal update example.