This table provides the relationships between building outlines within mainland New Zealand when buildings are split or merged.

A building outline is a 2D representation of the roof outline of a building which has been classified from LINZ aerial imagery using a combination of automated and manual processes to extract and refine a building roof outline.

**Data vintage**

This dataset does not include building outline geometry, but provides the linkages between building_id's from different aerial imagery sources in the [NZ Building Outlines (All Sources)](https://data.linz.govt.nz/layer/101292) dataset when building outlines change from single outlines split into multiple outlines, and from multiple outlines merged as single outlines.

This dataset will be updated with changes in building_id relationships as new aerial imagery becomes available.

Please refer to the [NZ Building Outlines Data Dictionary](https://nz-buildings.readthedocs.io/en/latest/introduction.html) for detailed metadata and information about this dataset.

**Related building outlines data**

[NZ Building Outlines (All Sources)](https://data.linz.govt.nz/layer/101292) - directly related to this dataset, it contains all combinations of building outlines from multiple years of imagery that have existed since the beginning of this dataset.

[NZ Building Outlines](https://data.linz.govt.nz/layer/101290) - provides current building outlines only derived from the latest LINZ aerial imagery.