Hi Xavier,

Check if this stair is IfcStair or IfcStrairFlight in the first tab of Properties in FZKViewer - Element Properties.
If not - set it in Allplan in Attributes-function. You will need IFC-section in Attributes list and IFC-type as an attribute.
Also, you will probably need to match Allplan's attributes with IFC-attributes, you can do it in IFC-Export dialogue.
To understand what is a name of an attribute, you can look into IFC-specification, for instance, for Pset_StairFlightCommon: https://standards.buildingsmart.org/IFC/RELEASE/IFC4_1/FINAL/HTML/schema/ifcsharedbldgelements/pset/pset_stairflightcommon.htm

By this way, using defined IFC-type, you can transfer any defined type and needed attributes, even if it is not existed in Allplan naturally, as Pile, for example.

Regards,
Alexey

Hi Xavier,

Hmm... first of all, if you are talking about Qto_ (Quantity take-off) set then it is existing since IFC4 and only for IfcStairFlight:
https://standards.buildingsmart.org/IFC/RELEASE/IFC4_1/FINAL/HTML/schema/ifcsharedbldgelements/qset/qto_stairflightbasequantities.htm
There are only 3 values: Length, GrossVolume and NetVolume.

By the way, some basic values are included into Calculated Values - length in planview, width in planview, total height, surface area and volume. Problems are that there is not length by stairway and that X and Y are not Length and Width and it will provide wrong results as "length" and "width", if this stair is not going by X and especially if this stair will be rotated in the planview.
Another problem is that there are not such specific attributes in IFC - neither in Pset_StairCommon nor in Pset_StairFlightCommon, so you can't match Allplan's attribute with IFC-attribute, even if you would to do this.

It seems like only one solution is here - add User-defined attribute in Allplan and read this attribute in IFC as Allplan's attribute.

Best regards,
Alexey