Unit means a dwelling which has one or more dwellings or buildings (excluding a garage or carpark) above or below it, such as a flat, unit or apartment. The following information will help you fill in the Unit building details section of the BASIX assesssment.

Add unit building

Once the Project Type page has been filled, unit buildings can be added or removed only on the "Project details > Unit building details" page.


  1. Click on the button.
  2. In the popup window, enter the number of buildings you want to add.
  3. Click on the button.

The new building(s) will appear in the table on the Unit building details page. The BASIX tool only allows a total of 20 unit buildings. 

What is a building name?

The building name allows you to identify your buildings when using BASIX and aids in certifier identification of the building for inspecting commitments.

How do I change the building name?

The BASIX tool sets the building names by default. You can overwrite this with your own building names. How do I count the number of storeys in a unit building?


Storey means a space within a building that is situated between one floor level and the floor level next above, or if there is no floor above, the ceiling or roof above, but does not include:

  1. a space that contains only a lift shaft, stairway or meter room,
  2. a mezzanine, or
  3. an attic.

To determine the number of storeys in a unit building, count only those levels which: meet the definition of a storey, and are wholly or partly above ground, and, have spaces for uses other than as plant rooms and/or airconditioning equipment.

"Above ground" means that part of the level is above ground at some point around the perimeter of that level. It is the ground level of the proposed building and not for existing natural ground level.

The following examples CAN'T BE counted in the number of storeys:

  • underground basement carpark levels
  • levels on top of the building which only have plant rooms and/or airconditioning equipment such as cooling towers
  • top floor levels with only stair access to a terrace

The following examples CAN BE counted in the number of storeys:

  • carpark levels partly above ground for natural ventilation
  • top floor levels with penthouse apartments and plant rooms
  • ground floor or other levels with commercial, retail spaces
  • levels containing dwellings

Building with multiple unitsBuilding with multiple units