While communicating with a project partner I came upon a small discrepancy in the P_Set of Ramp and Stair. The LoadBearing parameter is defined in the list of the Property_Set but not in the small list directly found in the entity:
I can also see the problem.
@jonm - I have looked at the Git repo looking for where to fix this, but it looks correct to me. If you can point out where I might make the change, I can submit a PR.
I have checked
Sections/Shared\ element\ data\ schemas/Schemas/IfcSharedBldgElements/PropertySets/Pset_RampCommon/DocPropertySet.xml and the property is there and it says it is applicable to