floorLevel

This term is proposed for full integration into Schema.org, pending implementation feedback and adoption from applications and websites.

Thing > Property > floorLevel

The floor level for an Accommodation in a multi-storey building. Since counting systems vary internationally, the local system should be used where possible.
Values expected to be one of these types
Text
Used on these types
Accommodation

Source

https://github.com/schemaorg/schemaorg/issues/2373