Understanding Building Classes Under the National Construction Code (NCC)

A Practical Guide to Classes 1–10

If you work in construction, architecture, property development, or you’re simply looking to understand building compliance in Australia, knowing how National Construction Code building classes work is essential.

The National Construction Code classes categorise buildings according to use, safety requirements and occupancy type: a framework that ensures every structure is built to an appropriate standard.

Although NCC building classifications may seem technical at first, the system quickly becomes logical once broken down. This guide explains each class in plain language with examples, making it easier for builders, designers and property owners to reference when planning projects.

What Are NCC Building Classes?

The NCC building classifications system groups buildings into ten categories based on how they are used, how people occupy them, and the risk profile associated with that use. Residential houses, commercial offices, factories and public buildings all serve different purposes, so the construction requirements they must meet also differ.

In simple terms:
A home doesn’t need the same fire performance as a hospital, and a warehouse doesn’t require the same accessibility standards as a school.

Classes 1 to 10 cover the majority of Australian building classifications, from everyday homes and apartments to hospitals, factories, storage buildings and non-habitable structures.

NCC Building Classifications Explained

Below is a practical breakdown of NCC building classes (Class 1–10) and what each classification means.

Class 1 – Residential Housing

Buildings used primarily as private homes.

Sub-classes:
• Class 1a – A standalone dwelling or one in a row of attached homes such as terrace houses, townhouses or duplexes.
• Class 1b – Small accommodation buildings (generally up to 300m²), including small hostels, guesthouses or bed-and-breakfast style stays.

Class 2 – Apartments

Buildings containing two or more sole-occupancy units positioned side-by-side, above or below one another. This includes apartment buildings as well as units above shared spaces such as carparks and basements.

Class 3 – Larger Residential Accommodation

Used for residential purposes where occupants are unrelated or transient.

Examples include:

boarding houses
hostels and backpacker accommodation
student housing
workers’ quarters
hotels and motels
residential care buildings

Class 4 – A Residence Within a Non-Residential Building

A single dwelling located inside another building.

For example, a caretaker’s unit within a hospital or a manager’s apartment above a shop. Only one dwelling can exist under Class 4 within a single structure.

Class 5 – Office Buildings

Buildings used for clerical, commercial or professional work, including government offices, law firms and administrative workplaces.

Class 6 – Retail & Customer Service Buildings

Premises where goods are sold, or services are directly provided to the public.

Examples:

retail shops and shopping centres
restaurants and cafés
barber shops and hair salons
laundromats
showrooms
funeral parlours

Class 7 – Storage & Warehousing

Buildings used for storing goods or vehicles.

Sub-classes:
• Class 7a – Carparks
• Class 7b – Warehouses, wholesale storage facilities or distribution spaces

Class 8 – Industrial & Production Buildings

Buildings where products are manufactured, assembled, processed or altered.
This includes factories, workshops, abattoirs and laboratories — often requiring higher levels of safety and fire protection.

Class 9 – Public & Community Use Buildings

Designed to accommodate or serve groups of people.

Sub-classes:
• 9a – Healthcare (hospitals, clinics, day surgery centres)
• 9b – Assembly buildings (schools, universities, theatres, places of worship, halls, sports centres)
• 9c – Aged care facilities

Class 10 – Non-Habitable Structures

Structures not designed for residential use.

Sub-classes:
• 10a – Private sheds, garages or carports
• 10b – Fences, masts, antennas, retaining walls, swimming pools
• 10c – Private bushfire shelters associated with a Class 1a dwelling

Why Classification Matters

Correct building class compliance affects:

fire safety and structural requirements
certification and approval pathways
access and egress requirements
engineering and material specifications
insurance and risk assessment

Using the wrong classification can lead to approval delays, redesign costs, or safety issues. Identifying the correct NCC building class early reduces risk and ensures smoother development.

Mixed-Use Buildings

Some buildings fall under more than one class.
A common example is a ground-floor retail shop with apartments above.

Level/Use	Building Class
Retail shop	Class 6
Residential apartments	Class 2

Mixed-use projects are common in modern Australian building classifications, and each component must meet the requirements relevant to its function.

Quick Reference Summary

NCC Class	Typical Use
1	Houses, townhouses, small accommodation
2	Apartments & multi-unit residential
3	Hotels, hostels, student and boarding housing
4	Single dwelling within non-residential building
5	Office & administrative workplaces
6	Retail shops, restaurants & service businesses
7	Storage facilities & carparks
8	Industrial/manufacturing premises
9	Public buildings – healthcare, assembly, aged care
10	Non-habitable structures (sheds, pools, shelters)

Understanding NCC building classes makes construction compliance simpler and helps ensure buildings are safe, efficient and appropriately designed. Whether you’re planning a residential build, renovating a commercial site or designing a warehouse, referencing this NCC building class guide early supports smoother approvals and better project outcomes.