Open Project BIM Settings and start a new property set group.
On the Export ribbon tab, in the BIM Exports group, click Project BIM Settings, then expand Use LD3-Project Specific BIM Properties. Click New Property Set Group. In the Edit BIM Property Set Group dialog, enter a Group Name and a Sort index (controls the group's display order), then click OK.
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Add a property set to the group.
Click New Property Set. In the Add BIM Property Set dialog, enter a Name and Description, then check which IFC version(s) (4.3 / 4.0 / 2x3) and LOD(s) (100 through MAX) this set applies to. Optionally check Use only for and pick a specific IFC object type (e.g. IfcObject) to scope the whole set to that one IFC entity.
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Add a BIM Property and set its name, type, and unit.
Click New BIM Property. Fill in:
- Name — a clear, distinct parameter name, e.g. Car_WIDTH.
- Type — the data type of the value. See BIM Property Type table.
- Unit — click the … button and choose the matching unit category from the Liftdesigner database (e.g. "mm or inch (Project Length)").
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Configure the Export Type Settings.
Expand Export Type Settings.
- IFC-Export Type — pick the closest IFC value-type preset for this property (e.g. IfcQuantityLength, IfcLengthMeasure) from the searchable list, or check Custom to enter your own.
- Revit Parameter — choose Type or Instance, i.e. whether the value is fixed for the whole family or can differ per placed instance in Revit.
- Revit Shared Type — leave at "0: Not a shared parameter" for a normal Revit parameter, or pick a shared-parameter data type (Text, Integer, Length, Area, Volume, Angle, Currency, and others) if your recipient needs it registered as a Revit shared parameter.
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Configure the Optional Property Settings.
Expand Optional Property Settings.
- Description / Comments — free text shown as tooltips in both Liftdesigner and Revit; use it to explain the property to whoever reads or fills it in later.
- Mode — leave at "Standalone Property" for an independent value. Use "Minimum of a Range", "Maximum of a Range", or "Typical Value in a Range" for a set of properties that together describe one numeric range (give them all the same Name); use the 2D/3D Vector options for coordinate components.
- ID — a unique identifier is generated automatically; only edit it if this property must map onto an ID already used by another piece of software.
- Valid for — refine the IFC version(s)/LOD(s) this specific property applies to. This must stay inside the range set for the whole property set in step 2 — e.g. a set valid for LOD 200–300 cannot contain a property valid only at LOD 400.
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Assign the property to component types, give it a value, then save.
Expand Add LDX Types to have the "<property name>" Property, then click Add LDX Types. In the category tree (e.g. Typical Important Components, Car, Shaft Building Elements), check every component type (LDXType) that should carry this property — for example LDXCar — or check "Add this property to all LDXtypes" to apply it everywhere at once.
- For each LDXType you added individually, either type a static value, or click the pencil icon to open the rule editor and enter a parametric formula (e.g. LD("Document.Shaft0.Car.CW")) that pulls the value live from the model.
- If you used "Add this property to all LDXtypes" instead, set one shared Default Value for all of them.
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Click OK to close the property, then OK again to close the property set. Back in the main dialog, confirm every component type you assigned the property to is also checked under Select component types to have BIM Properties (see "Set Up Project BIM Settings for Export") — otherwise the property is silently left out of the export. Optionally click the save icon next to Project BIM Settings: to store the whole configuration as a reusable preset, then click OK to apply.