The data presented in these design dashboards is only for residential buildings.


NCC Building Class – Building class numbers and percentage by State/Territory

Floor and Window Areas – Conditioned floor areas and window areas by State/Territory

Project type – Project type numbers and percentage by State/Territory

Dwelling Zones – Zone distribution in dwellings by State/Territory based on FirstRate5 certificates only

Certificate trends – Monthly number of certificates and average star rating by State/Territory

NCC Class

Within the NCC residential buildings are divided into several different class types, these are:

  • Class 1a – A single dwelling that is either a detached house or one of a group of two or more attached dwellings, each being a building, separated by a fire-resisting wall, including a row house, terrace house, town house or villa unit.
  • Class 1b – a boarding house, guest house or hostel.
  • Class 2 – A building containing 2 or more sole-occupancy units each being a separate dwelling, such as, apartment buildings and flat/unit developments.
  • Class 4 – A dwelling in a building that is not a residential building, i.e. it is the only dwelling in the building. A caretaker’s residence in an office building is an example of this.

The dashboards only cover class 1a, class 2 and class 4 dwellings. Class 1a dwellings are simplified to class 1 in the dashboards. Class 4 are included, but are very small in number and in many areas there will not be sufficient in number to display data on.

Project Type

In addition to new dwellings requiring to meet NCC energy efficiency requirements, the code also requires that major modifications, renovations, additions and alterations to residential buildings also meet the energy efficiency requirements and consequently NatHERS ratings are undertaken for this type of work. Existing dwellings are also sometimes rated at the request of the building owner, but there is no mandatory requirement to rate existing buildings in Australia.

Site Exposure

The NatHERS simulation that is undertaken takes into account the exposure of the building to wind, which has an impact on the energy efficiency if the building . A general classification of site exposure is entered by the assessor and these are:

  • Exposed – Exposed open terrain; few or no obstructions. Flat grazing land, lake side, ocean frontage, desert and exposed high-rise unit above 10 floors are examples of this.
  • Open – Open terrain; grasslands with few well-scattered obstructions below 10 m. Farmland with scattered sheds, lightly vegetated bush blocks and medium-rise unit above 3 floors are examples of this.
  • Suburban – Suburban housing and heavily vegetated bushland areas are examples of this.
  • Protected – Numerous closely spaced obstructions over 10 m. City and industrial areas are examples of this.
Nationwide House Energy Rating Scheme
Supported by data from the Nationwide House Energy Rating Scheme (NatHERS)