Building Classifications

The various requirements of the NCC respond to the various building profiles that exist in Australia. The use of the building, reflected in the NCC classification system, is one part of a building profile that determines which provisions apply.

Information about building classification is located in Section A6 of the Governing Requirements across all 3 volumes of the NCC. Explanatory information in Section A6 discusses the distinctions between the classifications and gives useful examples.

You can find more information on this topic in NCC Navigator: Building Classifications and NCC Tutor lesson: Understanding Building Classifications, both available on the ABCB website.

The appropriate authority, often a building certifier or surveyor, is responsible for determining what building classification applies to a specific development.

If the most appropriate classification for a building is not immediately clear, the appropriate authority must classify the building as belonging to the class it most closely resembles. In these circumstances, state and territory authorities for building regulatory matters may have issued specific advice that the appropriate authority may find useful.

A mixed-use development, where various parts of the same building have various uses, will have multiple classifications applied to it. This is because A6G1(2) requires that each part of a building be classified according to its purpose (subject to some exemptions). Therefore, for example, a building might include apartment levels (Class 2) above ground-level shops, restaurants and cafes (Class 6) and a basement carpark (Class 7a).

Yes, A6G1(1) requires that the classification of a building, or part of a building, be determined by the purpose for which it is designed. Sometimes, a building is developed before it is tenanted and is designed for various purposes attracting multiple classifications. For example, an industrial building designed for use as a factory or warehouse can simultaneously be classified as Class 7b and 8 providing it complies with all requirements applicable to these classifications (A6G1(2)).

A6G1 has an exemption that permits a minor part of a storey to take the building classification of the major part where the minor part’s floor area is less than 10% of the floor area of the storey it is situated in. However, this exemption cannot apply where the use of the minor part is a laboratory, early childhood centre, or Class 2, 3 or 4 part of a building.

Note, this exemption is optional; it is possible to apply the separate classification if desired.

Most existing buildings in Australia have been subject to building approval, for which a building classification will likely have been applied. Therefore, when seeking to find the classification of an existing building, we recommend you check the relevant building approval documentation. This information is normally accessible via your local council. 

Sole-occupancy unit (SOU) is a defined term in the NCC.  It refers to a part of a building for occupation by a person or group to the exclusion of others. Examples include a single apartment within a Class 2 apartment building and a single shop within a Class 6 shopping centre. A Class 4 part of a building, by virtue of being a dwelling alongside another classification, is also a SOU. 

State and territory legislation specifies what regulations (if any) apply to a garden shed. Therefore, we recommend you contact your local council or the relevant state or territory building administration.