This objectified relationship relates a space object to one or many coverings, which faces (or is assigned to) the space. 

The IFC specification provides two relationships:

• IfcRelCoversBldgElements to assign coverings to elements.
• IfcRelCoversSpaces to assign coverings to spaces.

Whether the relationship between the covering and the space, or between the covering and the element, is regarded as primary, has to be determined within the context of a model view definition.

• NOTE: Particularly floorings, ceilings and wall coverings, such as claddings or tiling are often considered as space coverings, rather then wall or slab coverings. In some life cycle phases, such as the operation phase, the relationship is always made to the space.

changes 

• IFC4 changes:
  • Name of the RelatedSpace attribute changed from RelatedSpace to RelatingSpace.
  • The relationship IfcRelCoversSpace is now deprecated, use IfcRelContainedInSpatialStructure instead.