Hierarchy classification:

1. top of the aat hierarchies
2. Objects Facet
3. Built Environment (hierarchy name)
4. Single Built Works (hierarchy name)
5. single built works (built environment)
6. [single built works by specific type]
7. [single built works by function]
8. residential structures
9. dwellings
10. multiple dwellings

Anotations

Scope note:

Multiple dwellings comprised of three housing units in a row, each with its own ground-level entry; for dwellings in which three housing units are stacked one above the other, use "three-deckers (dwellings)." For apartments with rooms on three levels, use "triplexes (apartments)."