# Common Property Sets

**Export IFC common property sets** exports the default properties defined in the IFC schema and is activated by default. Existing Revit properties are automatically mapped to the IFC properties.

The common property sets can be recognized by the Pset\_ prefix after the export:

<figure><img src="/files/YlVMrdjH7blCrFbo5Goe" alt=""><figcaption></figcaption></figure>

As the IFC schema contains many properties which are not commonly used in all projects and therefore not included in Revit by default, only a subset of the properties defined in a Pset will be exported using this option. The complete Pset\_ WallCommon includes several properties not existing in Revit by default:

<table><thead><tr><th>Property</th><th>Description</th><th data-hidden></th></tr></thead><tbody><tr><td>Reference</td><td>Component type (type name)</td><td></td></tr><tr><td>AcousticRating</td><td>Sound insulation clalss</td><td></td></tr><tr><td>FireRatingCombustible</td><td>Fire-resistance class (type parameter)</td><td></td></tr><tr><td>SurfaceSpreadOfFlame</td><td>Fire behavior</td><td></td></tr><tr><td>ThermalTransmittance</td><td>U-value (type parameter)</td><td></td></tr><tr><td>IsExternal</td><td>Exterior component (type parameter, given as yes/no)</td><td></td></tr><tr><td>ExtendToStructure</td><td>Fixed on top (behavior)</td><td></td></tr><tr><td>LoadBearing</td><td>Load bearing (instance parameter)</td><td></td></tr><tr><td>Compartmentation</td><td>Fire compartment-defining component</td><td></td></tr></tbody></table>

There are several options to add these properties. The first and the most simple one is by adding the properties with the same name and data type as defined in the IFC schema to Revit. The easiest way to accomplish this is by using the IFC shared parameters file already introduced in this manual (see: Using IFC Shared Parameters). This will make sure that the spelling and the data type are correct. Once these properties have been added and populated, they will be automatically added to the Pset upon export:

<figure><img src="/files/paVzvaQpxefhoHJYAfOz" alt=""><figcaption></figcaption></figure>

Alternatively, it is possible to [map other properties](/revit/ifc-export-settings-dialog/property-sets/parameter-mapping-table.md) (as long as they have the same data type) to the corresponding IFC properties.

Following video provides an overview of the topics discussed in this section: \ <mark style="background-color:orange;">▶️</mark> [<mark style="background-color:orange;">Exporting IFC Common Property Sets from Revit</mark> ](https://youtu.be/5q6Egq9tthE?si=V1ZfyQMh4tpgY9CF)


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