Product(s):	OpenBuildings Designer (and AECOsim Building Designer)
	Version(s):	CONNECT Edition and V8i
	Area:	Import/Export
	Subarea:	IFC

When working with IFC Mapping it is important to understand a couple of concepts that lie behind the mapping of Catalog (DataGroup) properties to IFC definitions and Psets:

• Catalog Types: These define objects that belong to the same category, for example walls, doors, windows, etc.
• Catalog Item: This is a member of a Catalog Type so would be a specific definition of a wall, door or window.

Out of the box we provide some default settings that in the first instance are applied to each Catalog Type and inherited by the Catalog Items within that Catalog Type. Users can review these out of the box assignments in the export dialog box.

Users can also change the mapping for Catalog items both at the Catalog Type level and at the Item type level. 

These overrides can be stored centrally so any user working on the project can use consistent settings for export.

We also provide the ability to create this override at the object definition level in the Catalog system (below). This override will take precedence over the mapping table above. Out of the Box we use the dialog above, not providing overrides at object level, as it gives an overview on the entire Catalog system.

If assignments are found that do not meet project or other requirements they can be be resolved by reviewing the mapping dialogs or Catalog entries. Our datasets and the mapping tables contained within them are examples that will not always cover all of the objects encountered in live project work.