The NCC 2019 - Vol 1 contains technical design and construction requirements for all commercial buildings (multi-residential, commercial, industrial, and public assembly buildings) and their associated structures.
These buildings include the following:
1a - A single dwelling being a detached house, or one or more attached dwellings, each being a building, separated by a fire-resisting wall, including a row house, terrace house, townhouse or villa unit.
1b - A boarding house, guest house, a hostel or the like with a total area of all floors not exceeding 300m2, and where not more than 12 reside, and is not located above or below another dwelling or another Class of building other than a private garage.
2 - A building containing two or more sole-occupancy units, each being a separate dwelling.
3 - A residential building, other than a Class 1 or 2 building, which is a commonplace of a long term or transient living for a number of unrelated persons. Example: boarding-house, hostel, backpackers accommodation or residential part of a hotel, motel, school or detention centre.
4 - A dwelling in a building that is Class 5, 6, 7, 8 or 9 if it is the only dwelling in the building.
5 - An office building used for professional or commercial purposes, excluding buildings of Class 6, 7, 8 or 9.
6 - A shop or other building for the sale of goods by retail or the supply of services direct to the public. Example: café, restaurant, kiosk, hairdressers, showroom or service station.
7 - Class 7a - A building which is a car park.
7b - A building which is for storage or display of goods or produce for sale by wholesale.
8 - A laboratory or a building in which a handicraft or process for the production, assembling, altering, repairing, packing, finishing or cleaning of goods or produce is carried on for trade, sale or gain.
9 - A building of a public nature. Class 9a - A health care building, including those parts of the building set aside as a laboratory.
9b - An assembly building, including a trade workshop, laboratory or the like, in a primary or secondary school, but excluding any other parts of the building that are of another class.
9c - An aged care building.
10 - A non-habitable building or structure.
10a - A private garage, carport, shed or the like.
10b - A structure being a fence, mast, antenna, retaining or free-standing wall, swimming pool or the like.
10c - A private bushfire shelter.
Where it is unclear which building classification should apply, Appropriate Authorities have the discretion to decide.
In some cases, multiple buildings can be considered as united buildings, potentially altering some Performance Requirements. Buildings are deemed united when two or more buildings adjoining each other are connected and used as one building.
United buildings are not required to comply with additional NCC provisions. For example, any new openings do not require any form of fire protection not required of a single building. However, an external wall, which, as a result of interconnection becomes an internal wall, must comply with the requirements for an internal wall.
Interconnected buildings that do not jointly comply with all the requirements applicable to a single building remain as separate buildings.