The basic unit underpinning these counts are land parcels, which are the smallest units of land that can be bought and sold. For most purposes, these are the basic unit for land administration and development.
Land parcels are recorded by states and territories in land administration systems called cadastres. These capture boundaries, ownership, rights, and restrictions that apply to land parcels. Cadastres can also be represented spatially as maps that show the boundaries of all the registered land parcels across an area. These cadastral maps are the data source for land parcel information used to produce these indicators.
Land parcels may only have one title of ownership issued, but in certain cases where there is shared ownership for common property, there may be multiple titles. In these situations the parcel is further divided through a strata plan into private units and common property. These strata parcels are often captured in cadastral maps, however counts presented in this publication only reflect the underlying land parcels they sit on top of.
In some states and territories, parcels are created for public infrastructure like roads. These have been excluded as an input into the counts presented in this publication.
Building approvals are issued as part of the normal administrative building approval process. The ABS collects these primarily from local government authorities, but also from other principal certifying authorities including commonwealth, state, and semi-government authorities.
The approvals used in this publication cover all approved residential building work valued at $10, 000 or more, where new dwellings will be constructed as part of the development. It excludes approvals for dwellings that will be attached to existing structures, or converted from a non-residential building to residential, known as "Alterations and additions" or "Conversions" respectively.
Building approvals are provided with address information which can be used to identify the location of the building work in most cases. This has been utilised for this publication to associate building work with a building site and area and local zoning information.