What is UBID?

UBID is a standard for uniquely identifying building footprints on the Earth.


The UBID for a building footprint has five components:

  1. The Open Location Code for the geometric center of mass (i.e., centroid) of the building footprint.
  2. The distance to the northern extent of the bounding box for the building footprint in Open Location Code grid units.
  3. The distance to the eastern extent of the bounding box for the building footprint in Open Location Code grid units.
  4. The distance to the southern extent of the bounding box for the building footprint in Open Location Code grid units.
  5. The distance to the western extent of the bounding box for the building footprint in Open Location Code grid units.

Abstract

Measuring and tracking building energy use and other data is essential for cities, utilities, and service providers. Currently, buildings are conceived as "destinations" and therefore are identified with street addresses or with a single geographic coordinate point (latitude and longitude). However, the address-based system is insufficient to uniquely identify buildings, and to append and join data from disparate sources due to address name duplicates, incorrect entries, and lack of an input format standard. Other industries have implemented unique identifiers to handle the increasing amount of data that is appended to those identifiers. Similarly, we developed UBID to act as an external common key between databases and to facilitate data mapping. Our methodology converts a building footprint into a unique identifier based on a grid reference system. The developed ruleset ensures that individual implementers can reach the same conclusion utilizing publicly available digital maps. We generated UBIDs for all buildings in three major US cities (San Francisco, Chicago, and New York City) and performed statistical analysis to verify the uniqueness and effectiveness of the proposed unique identifier.