Definitions›no specific standard›attributes›identification›reference point
singularity of a structure
Guidelines for distinguishing an individual building from its built context.
a) If two towers equivalent to high-rises or skyscrapers are separated for at least 2/3 of the lower one's height, they are considered separate UNLESS the connection(s) between them form an unmistakable architectural unity. Normally a simple skybridge between them does not form a unity, but a bridged top (such as Genex Tower, Dusit Dubai, or Umeda Sky Building) suffices to constitute a single building.
b) Any structures which adjoin each other for more than 1/3 of any of their heights should be considered one building UNLESS: 1) they were built as separate structures and neither one can be considered an addition to the other; this means that the interiors are not integrated at any level, including the ground floor or basement; or 2) the structures are separated at ground level and connected for most of their heights but are normally considered separate buildings; or 3) an addition to a building forms a significant architectural disjunction.
c) An addition on top of an existing building, with any kind of vertical connection between them, is never counted as a separate building from the one underneath.
d) When a multi-unit building is attached to subsidiary units (e.g. an apartment building attached to townhomes), the subsidiary units are considered separate from the main building unless they are vertically integrated into its architecture or otherwise deemed architecturally inseparable.