Hierarchy classification:

1. top of the aat hierarchies
2. Objects Facet
3. Components (hierarchy name)
4. components (objects parts)
5. [components by specific context]
6. architectural elements
7. [structural elements and components for structural elements]
8. structural elements
9. structures (structural elements)
10. [structures by location or context]

Anotations

Scope note:

Support systems and areas of buildings or other structures located below ground level or at the lower portions of structures when distinguishing these portions from the above ground or upper levels, in which case use "superstructures." Use "foundations (structural elements)" specifically for those parts of structures, usually below ground, that transmit loads to the supporting earth or rock.