Understanding Building Classes in the National Construction Code.

The National Construction Code (NCC) of Australia serves as a comprehensive guide for building standards and regulations, ensuring safety, sustainability, and livability across various types of structures. Central to the NCC is the classification of buildings into specific classes based on their intended use and occupancy. This classification system is crucial for architects, builders, developers, and regulators to adhere to appropriate construction standards and requirements.

Class 1: Residential Buildings

Class 1a: Comprises single dwellings, either detached houses or attached dwellings such as townhouses and terrace houses. These are common residential buildings designed for families or individuals.

Class 1b: Encompasses small boarding houses, guest houses, and hostels with a maximum of 300 square meters in floor area and not more than 12 occupants. This class addresses shared accommodation facilities.

Class 2: Apartment Buildings

These buildings contain multiple sole-occupancy units, each being a separate dwelling. Class 2 buildings include apartment complexes and condominiums, catering to multi-family housing needs.

Class 3: Long-Term or Transient Accommodation

Includes buildings used for long-term or transient accommodation of unrelated persons, such as hotels, motels, large boarding houses, and certain residential parts of schools. This class ensures appropriate safety and amenity standards for various forms of collective living arrangements.

Class 4: Mixed-Use Buildings

Refers to a single dwelling within a building that otherwise falls under Class 5, 6, 7, 8, or 9. An example is a caretaker’s residence in a commercial building, highlighting the need for integrating residential spaces within non-residential structures.

Class 5: Office Buildings

Encompasses buildings used for professional or commercial purposes, excluding retail. This includes typical office buildings, administrative buildings, and commercial offices, where business operations are conducted.

Class 6: Retail and Commercial

Includes shops and other buildings for retail sales or service provision to the public. This class covers a broad spectrum of commercial activities, including cafes, restaurants, shops, and showrooms.

Class 7: Storage and Wholesale

Class 7a: Refers specifically to car parks.

Class 7b: Encompasses buildings used for the storage or display of goods for wholesale distribution. This classification covers warehouses and large storage facilities.

Class 8: Industrial Buildings

Buildings where manufacturing, processing, or other industrial activities occur. This class ensures that facilities like factories and laboratories adhere to stringent safety and operational standards.

Class 9: Public Buildings

Class 9a: Health care buildings such as hospitals and clinics where medical care is provided.

Class 9b: Assembly buildings used for gatherings of people, including schools, theaters, and places of worship.

Class 9c: Aged care buildings designed to accommodate elderly residents, ensuring specific safety and accessibility features.

Class 10: Non-Habitable Structures

Class 10a: Private garages, carports, and sheds.

Class 10b: Structures like fences, masts, antennas, and swimming pools.

Class 10c: Private bushfire shelters, providing safety in bushfire-prone areas.


The NCC’s building classification system plays a vital role in the construction industry by delineating standards and requirements tailored to the specific functions of buildings. Understanding these classes helps industry professionals ensure that buildings meet the necessary safety, health, and sustainability criteria. As the construction landscape evolves, staying informed about these classifications is crucial for delivering compliant and high-quality projects.