GUIDE: NEW: Building Code Australia: Co-Living Compliance Guide

Building Code Australia: Co-Living Compliance Guide

Building Code Australia requirements can have a direct impact on whether a house can be converted into co-living accommodation, how many people it can accommodate, what upgrades are needed and which approvals must be obtained before residents move in. For property investors, understanding the compliance pathway early is important because a design that works financially on paper may need to change once building classification, fire safety, accessibility, planning and state-specific operating rules are taken into account.

The official term is the Building Code of Australia (BCA), which forms Volumes One and Two of the National Construction Code. The NCC is Australia’s primary technical framework for building design and construction, covering matters such as structure, fire safety, access and egress, accessibility, health, amenity and sustainability. It is produced by the Australian Building Codes Board and then given legal effect through state and territory legislation.

For co-living investors, Building Code Australia compliance should be considered before a property is purchased, before a room count is locked in and before renovation drawings are finalised. That does not mean investors need to interpret the code themselves. The better approach is to bring the relevant building certifier or surveyor, designer, planner and construction specialists into the feasibility process at the right time.

INVIDA takes this coordinated approach when assessing co-living conversions and custom-built co-living homes. The aim is to understand the likely approval pathway early, identify constraints before they become expensive and design the investment around both tenant demand and compliance.

This guide explains the national building-classification framework and the additional considerations that apply in Queensland, New South Wales, Victoria and Western Australia. Requirements can differ by state, council, property and project, so the information below should be treated as a general guide rather than project-specific building or legal advice.

Is Co-Living Right for You?

We’ll walk you through our proven co-living investment model, answer your questions, and show you how to maximise rental returns.

What Building Code Australia Means for Co-Living

One of the first questions in co-living compliance is not whether the property is marketed as a “co-living home”. It is how the building will actually be classified under the NCC.

The NCC classifies buildings according to their purpose and use. A standard detached house is usually Class 1a. A small boarding house, guest house, hostel or similar building may qualify as a Class 1b building if it would ordinarily accommodate no more than 12 people and has a total floor area of no more than 300 square metres. Larger shared-accommodation buildings can fall into Class 3. A building containing two or more sole-occupancy units, where each unit is a separate dwelling, can fall into Class 2.

This matters because Building Code Australia classification determines which technical provisions apply. A property does not automatically become Class 1b merely because bedrooms are rented separately, nor does calling a development “co-living” determine its BCA class. The approved design, intended use, relationship between private and common areas, occupant numbers and whether any units operate as separate dwellings all need to be considered.

The NCC also explains that a building can remain Class 1 or Class 2 when any number of unrelated people jointly own or rent it. In other words, the presence of unrelated occupants alone does not make a property Class 3. This is an important distinction when comparing an ordinary share house with accommodation operated more like a boarding house, lodging house or other room-by-room accommodation business, where the building’s actual use and operating arrangement can affect its classification.

How Building Code Australia Separates Class 1a, Class 1b, Class 2 and Class 3

For investors assessing a potential co-living conversion, the practical distinction is:

Class 1a: usually a detached house or an attached dwelling such as a townhouse.
Class 1b: a small boarding house, guest house, hostel or similar accommodation within the NCC’s occupancy and floor-area limits.
Class 2: a building containing two or more sole-occupancy units, each being a separate dwelling.
Class 3: residential accommodation for a number of unrelated people that does not fall within Class 1 or Class 2, including larger boarding houses, hostels and lodging houses.

A Class 1 building also cannot generally be located above or below another dwelling or another class of building, other than a private garage. This can become relevant when investors consider mixed-use buildings, shop-top accommodation or conversions involving commercial space.

Classification should be confirmed by the relevant building certifier, building surveyor or approval authority. It should not be assumed from the real estate listing, the number of existing bedrooms or the way a previous owner used the property.

Building Code Australia Requirements for Co-Living Conversions

Converting an existing house for co-living should begin with a review of what the property was approved for and how the proposed accommodation will change its use. The scale of the renovation is only part of the question. A relatively modest building project can still have important compliance implications if the finished property will operate differently from a conventional home.

The National Construction Code generally applies to new construction, but existing buildings can also come within its scope when they are altered, extended or undergo a change of use. For an investor planning a co-living conversion, this means the existing approval history, proposed resident numbers, room configuration and intended operating model should be examined before the design and construction budget are finalised.

Building Code Australia compliance can therefore influence the feasibility of the investment well before construction starts. The objective is not simply to determine whether additional bedrooms physically fit inside the property. It is to establish whether the proposed use can be achieved within an appropriate building classification and at a cost that still supports the investment strategy.

When Does an Existing Home Need a Building Code Review?

A typical house starts life as a Class 1a dwelling. If it is later adapted to operate as room-by-room accommodation, the relevant certifier or building surveyor may need to determine whether the proposed use changes the building’s classification and what approvals or upgrades follow from that change.

The assessment can take into account matters such as:

how many residents the property is designed to accommodate;
whether rooms are occupied separately or the home is rented jointly;
the amount of floor area;
how kitchens, bathrooms and common areas are arranged;
whether any rooms function as independent dwellings;
the extent of proposed structural or building work; and
whether another building classification or use exists on the site.

This distinction is important because an ordinary share house is not automatically the same as a boarding house, hostel or other rooming-style property under the NCC. Likewise, describing a project as “co-living” does not establish its classification.

Where the proposed accommodation falls within the definition of a Class 1b building, the property would ordinarily accommodate no more than 12 people and have no more than 300 square metres of total floor area. If those limits are exceeded, similar shared accommodation may instead need to be assessed as Class 3.

Confirming that position early gives the investor a more reliable basis for deciding whether the property is worth progressing.

What Can Change When the Classification Changes?

A change from a conventional Class 1a dwelling to shared accommodation can introduce requirements that were not part of the home’s original design.

For a Class 1b property, for example, the NCC contains more extensive smoke-alarm and evacuation-lighting requirements than those applying to an ordinary Class 1a house. Smoke alarms are required in every bedroom as well as specified circulation areas, and a lighting system is required to assist occupants during an evacuation.

Accessibility can also influence the design. The NCC’s access provisions for Class 1b accommodation can require access to an appropriate bedroom and associated sanitary facilities, together with access to relevant shared spaces. The exact requirements depend on the type of Class 1b development and the circumstances of the project.

Plumbing and drainage also form part of the compliance picture. The ABCB notes that Class 1b projects can require reference not only to the housing provisions but also to Volume One for certain fire and accessibility matters and Volume Three for plumbing and drainage.

For an investor, these are not simply technical details for the builder to resolve later. They can affect:

where bedrooms can practically be positioned;
whether an entrance or pathway needs modification;
bathroom and wet-area layouts;
electrical and alarm work;
circulation through common areas; and
the overall construction budget.

A design that produces another rentable room is not necessarily a stronger investment if achieving that room creates disproportionate compliance or construction costs.

Assess the Existing Property Before Locking In the Room Yield

Existing homes were rarely designed around a modern co-living operating model. That makes the condition and configuration of the original property particularly important during feasibility.

An assessment may need to consider the existing structure, ceiling heights, entrances, internal circulation, natural light, ventilation, wet areas, electrical capacity, drainage and the relationship between bedrooms and shared areas. Site conditions can also influence what is achievable.

For example, a large room may look suitable for subdivision into two bedrooms, but the finished spaces still need to work within the applicable requirements for light, ventilation, access and safe movement through the building. An unused part of the property may appear ideal for an ensuite until the location of existing plumbing makes the conversion disproportionately expensive. A steep entrance may also influence how practical an accessible pathway is to provide.

These issues are easier to solve while the project remains at the feasibility stage than after architectural plans, finance and construction pricing have been committed.

This is why INVIDA approaches adaptive reuse and property conversion as both an investment and a building exercise. The goal is to identify a room configuration that works commercially after the relevant constraints have been considered, rather than starting with the highest possible room count and attempting to make the compliance pathway fit around it.

For investors, that early assessment can create a clearer picture of the likely construction scope, achievable accommodation model and potential return before significant capital is committed.

Building Code Australia Compliance in Queensland

Queensland commonly uses the planning term rooming accommodation for accommodation where individual residents have a right to occupy one or more rooms but not the whole premises and share facilities with other residents.

The Building Code Australia framework and Queensland planning rules operate alongside each other. A property may satisfy the technical limits for a Class 1b building while still needing to meet separate state planning, building, plumbing, residential-service and council requirements.

As at August 2026, Queensland’s temporary streamlined planning provisions for certain small-scale rooming accommodation are scheduled to expire on 2 December 2026. The Queensland Government has made clear that the streamlined pathway does not remove other required approvals for building work, plumbing, drainage, registration or accreditation.

Queensland Planning Requirements

Under the current Queensland Planning Regulation rooming-accommodation provisions, certain rooming-accommodation projects can access a streamlined pathway where the prescribed conditions are satisfied.

Among the conditions are that the accommodation is provided in a Class 1 building, the premises are in specified residential zones, and the premises have no more than five bedrooms and are occupied by no more than five people. Other requirements deal with matters such as road access, hazard overlays, building work and landscaping.

This creates an important distinction for investors:

The NCC Class 1b limits can extend to 12 people and 300 square metres, while Queensland’s temporary small-scale planning pathway is capped at five bedrooms and five occupants.

Meeting one threshold does not mean the other approval test has been satisfied.

Investors considering a Queensland co-living investment should therefore check the applicable planning scheme, any overlays and the status of the temporary state provisions before relying on an expected room yield.

Registration and Accreditation in Queensland

Queensland also regulates certain residential services separately from planning and building approval.

Business Queensland’s residential-service guidance explains that a residential service generally provides accommodation to four or more residents who individually pay rent, occupy one or more rooms and share facilities. Where the Residential Services (Accreditation) Act applies, the service must be registered before it starts operating.

After registration is approved, the provider must apply for accreditation within three months. Level 1 accreditation is compulsory and addresses matters including privacy, residency agreements, resident safety, grievance processes, the living environment and residents’ independence.

A Queensland co-living feasibility review should therefore consider the complete operating pathway, not only the construction approval. Building classification, planning, residential-service obligations and the proposed leasing model need to work together.

Co-Living Building Requirements in New South Wales

New South Wales is different because the planning system specifically recognises co-living housing under the State Environmental Planning Policy (Housing) 2021.

NSW Government co-living housing guidance states that co-living housing must contain at least six private rooms, provide occupants with their principal place of residence and include shared communal space. It is distinct from a boarding house under the Housing SEPP, and co-living housing does not carry the same affordable-housing requirement that applies to boarding houses.

Development consent and the relevant Housing SEPP standards need to be considered separately from the BCA classification.

How the NSW Planning Definition Affects Building Classification

The NSW definition of co-living housing does not automatically make the building Class 1b or Class 3.

For example, a smaller proposal may sit within the numerical limits associated with Class 1b, but the certifier must still assess the actual design and use. Larger purpose-built co-living developments are more likely to be assessed as Class 3, while a project containing genuinely separate dwellings may raise Class 2 considerations.

The Housing SEPP contains standards dealing with private-room sizes, lot size, occupancy, communal space, management facilities and other design matters. Current NSW provisions include minimum private-room sizes, maximum occupancy of two people per private room and minimum lot-size requirements.

Local environmental plans and development controls may add further requirements around zoning, parking, setbacks, landscaping, waste and neighbourhood impacts.

The result is a two-part test:

Is the co-living use permissible and approvable under the planning framework?
What building classification and technical requirements apply to the approved design?

Both need to be resolved before an investor can rely on the final room count and construction budget.

NSW Fire Safety and Ongoing Compliance

NSW building owners also need to consider ongoing fire-safety obligations after construction.

From 13 February 2026, applicable essential fire-safety measures in Class 1b and Class 2 to Class 9 buildings must be inspected and tested in accordance with AS 1851-2012 unless an applicable performance solution provides another maintenance process.

NSW has also deferred NCC 2025 until 1 May 2027. The NSW Government NCC guidance states that the current edition is NCC 2022 Amendment 2, which took effect on 29 July 2025, subject to the rules that determine which edition applies to a particular application.

For investors, this reinforces why compliance is not a one-time construction exercise. The building needs to be designed, approved and maintained for the way it will actually operate.

Co-Living and Rooming House Requirements in Victoria

Victoria commonly regulates shared accommodation through its rooming-house framework.

Clause 52.23 of the Victoria Planning Provisions provides exemptions from certain planning-permit requirements for domestic-scale rooming houses where all prescribed conditions are met. The current use-exemption criteria include a total building floor area not exceeding 300 square metres, no more than 12 people accommodated and no more than nine bedrooms.

Victoria adopted NCC 2025 on 1 May 2026. Building practitioners must also consider Victorian building and plumbing regulations, which give effect to the NCC and any Victorian variations or transitional provisions.

Victorian Planning and Building Approval Requirements

The rooming-house planning exemption does not mean that no approvals are required.

The complete requirements of Clause 52.23 must be satisfied, and the site can still be affected by its zone, overlays, parking controls, building work and other local planning provisions. A planning-permit exemption also does not remove the need to address building approval or change-of-classification requirements where they apply.

For an existing Class 1a house being converted to a Class 1b rooming house, the building surveyor needs to determine what building work and evidence are required for the new use and classification.

This is why a Victorian investor should not treat “planning permit exempt” as equivalent to “ready to operate”.

Rooming House Registration and Minimum Standards

Victoria also has operating requirements beyond planning and building approval.

Rooming-house operators must be licensed, and rooming houses must be registered with the relevant local council. Consumer Affairs Victoria’s rooming-house guidance states that rooming houses are subject to minimum standards and public-health requirements covering matters including toilets and bathing facilities, hot and cold water, condition and cleanliness, smoke alarms, gas and electrical safety and other resident protections.

Local council registration can also involve prescribed-accommodation requirements. The planning exemption therefore removes only one potential approval step. It does not remove building, licensing, registration or ongoing safety obligations.

For investors, the strongest approach is to confirm the planning, building and operating pathway together before committing to a layout or purchase.

Western Australia Co-Living Property Compliance

Western Australia applies the national building classification system, but local planning and lodging-house requirements can play a particularly important role.

Western Australia adopted NCC 2025 on 1 May 2026 with state-specific variations. Building classification is still based on the purpose for which the building is designed, constructed or adapted to be used.

A small shared-accommodation property may potentially fall within Class 1b, while larger accommodation can fall within Class 3. Separate self-contained dwellings may raise Class 2 considerations.

The intended operating model should therefore be confirmed before design and approval work begins.

Approvals That May Apply in WA

Depending on the property and local government area, a Western Australian co-living project may need to consider:

development approval or change-of-use approval;
a building permit for proposed works;
evidence supporting a change of classification;
an occupancy permit where required;
plumbing and health requirements;
lodging-house registration; and
local rules dealing with occupancy, sanitary facilities, fire safety and management.

WA building-approval guidance notes that changing an existing Class 1a building to Class 1b requires the owner to notify the relevant permit authority and provide evidence that the building complies with the standards applying to the proposed classification. If building work is required to achieve that compliance, a building permit may also be needed.

WA legislation and local-government rules can also require lodging houses to be registered and inspected, depending on how the accommodation falls within the applicable definitions and local requirements.

Local requirements should be checked with the council responsible for the property. A process accepted in one municipality should not be assumed to apply unchanged in another.

For INVIDA investors, this is another reason to complete site and approval checks before construction commitments are made.

10 Checks to Complete Before Committing to a Co-Living Project

A promising property can lose its appeal quickly if planning, building or operational requirements are only investigated after purchase. Before committing to a co-living conversion or new build, investors should test the project from several angles to understand whether the proposed accommodation model is both achievable and commercially sensible.

1. Decide How the Property Will Actually Operate

Start with the intended use rather than the floor plan.

Consider how residents will occupy the property, whether bedrooms will be leased separately, what facilities will be shared and how much independence each room will provide. The proposed number of residents and the inclusion of features such as private bathrooms or cooking facilities can also affect how the project is assessed.

Having a clear operating model gives planners, designers and building professionals something specific to assess instead of relying on a general description such as “co-living”.

2. Establish the Building Classification Early

Before investing heavily in plans, obtain professional advice on the classification likely to apply to the completed property.

Depending on the design and use, a project may fall within Class 1a, Class 1b, Class 2 or Class 3, or involve more than one classification.

This is important because Building Code Australia requirements are linked to the actual use and configuration of the building. The name used to market the accommodation does not determine how it will be classified.

An early classification assessment can give investors a more realistic view of the technical requirements and construction scope before the project progresses too far.

3. Find Out What the Planning Scheme Allows

Building classification is only one part of the approval pathway.

The proposed accommodation also needs to be considered under the relevant state and local planning framework. Depending on the property and location, the project may require development consent, a material change of use application or another form of planning approval.

Zoning, room numbers, parking, setbacks, landscaping and the intensity of the proposed use may all influence what can be approved.

Checking planning requirements early helps prevent an investor from designing a project around an outcome the site may not support.

4. Look Beyond the Floor Plan When Assessing the Site

Two properties with similar internal floor areas can have very different development potential.

Before purchasing, investigate whether the site is affected by matters such as:

flooding or overland flow;
bushfire exposure;
cyclone or wind-design requirements;
heritage controls;
difficult topography;
protected vegetation;
limited vehicle or pedestrian access;
infrastructure limitations; or
planning overlays that restrict development.

These issues can add design complexity, approval conditions or construction costs that are not obvious during a standard property inspection.

5. Test Whether the Proposed Layout Still Works After Compliance Is Added

A concept plan should be tested against the requirements that will shape the finished property.

Rather than starting with a target number of bedrooms and forcing everything else around it, assess whether the layout still works once consideration is given to:

circulation through the property;
accessible areas where required;
bathrooms and sanitary facilities;
appropriate bedroom design;
kitchens and shared living areas;
light and ventilation;
fire-safety provisions;
laundry capacity;
waste storage; and
parking and access requirements.

Sometimes a slightly lower room count can result in a simpler approval pathway, a better resident experience and a more manageable construction budget.

6. Map Out the Approvals Needed for the Building Work

Once the proposed design is taking shape, identify which approvals are likely to be required before construction begins.

A conversion can involve more than a general renovation approval. Depending on the work, the project may include structural changes, extensions, additional bathrooms, plumbing alterations, drainage work and a change in building classification.

An existing house may also require upgrades before it is considered suitable for its proposed shared-accommodation use.

Understanding the approval pathway early makes it easier to build these costs and timeframes into the feasibility assessment.

7. Check What Is Required Before the Property Can Operate

Construction approval does not necessarily mean the property can immediately begin accepting residents.

Different jurisdictions can impose additional operating requirements for shared accommodation. Depending on the state, council and accommodation model, these may include:

registration of the premises;
accreditation of the accommodation service;
licensing of the operator;
lodging-house registration;
council approvals; or
an approved management plan.

These obligations vary significantly across Australia, so investors should identify the requirements that apply to the specific property rather than relying on the process followed for another project.

8. Understand What Compliance Looks Like After Opening

Some responsibilities continue for as long as the property operates.

Depending on the jurisdiction and classification, owners or operators may need to maintain fire-safety systems, arrange inspections, keep safety records, provide evacuation information and maintain required resident documentation.

These ongoing responsibilities should be understood before the investment is established because they can affect operating procedures and recurring costs.

A successful co-living project needs to remain compliant after residents move in, not simply achieve approval at completion.

9. Make Sure the Finance and Insurance Match the Finished Property

The proposed use of the property should also be discussed with the lender and insurer.

A home designed for multiple individual residents may be assessed differently from a conventional house occupied under a single household arrangement. Waiting until construction is complete to disclose the final use can create unnecessary complications.

Finance and insurance should therefore be considered as part of the project structure from the beginning, alongside planning and building requirements.

10. Design Around the Resident Experience as Well as Compliance

A compliant property still needs to be somewhere people want to live.

Consider how residents will use the home day to day, including:

privacy between bedrooms;
noise transfer;
storage;
internet connectivity;
utility arrangements;
security;
use of shared kitchens and living areas;
cleaning responsibilities; and
communication between residents.

These decisions can affect tenant satisfaction, retention and the way the property performs over time.

INVIDA’s co-living housing configuration guide explains how different combinations of private and communal spaces can influence the functionality and income potential of a co-living property.

Why Early Coordination Can Improve a Co-Living Investment

Co-living projects bring together several areas that are often handled independently in a conventional property purchase. The acquisition decision can affect planning. Planning can affect the design. The design determines the likely building classification, and that classification can influence construction, finance, insurance and the way the property is eventually operated.
Problems tend to arise when those decisions are made in isolation.
For example, an investor may purchase a property expecting to create a certain number of rentable rooms, only to discover that site constraints, access requirements or the planning framework reduce the practical yield. Another property may look difficult initially but become more attractive once the design is reworked around the site and approval requirements.
The value of early feasibility is that these questions can be investigated while the investor still has the flexibility to change direction.
Through INVIDA’s co-living investment process, property selection, design feasibility and the likely approval pathway can be considered as parts of the same investment decision. Investors can also compare the potential of converting an existing dwelling with the alternative of developing a purpose-built co-living home.
Qualified certifiers, building surveyors, planners and approval authorities still determine whether the project satisfies the requirements that apply to it. INVIDA’s role is to help bring those considerations into the investment process early enough to shape the strategy rather than becoming problems that need to be solved later.

Build the Investment Around What the Property Can Support

Building Code Australia compliance can influence much more than the construction phase of a co-living project. It can affect the type of property worth buying, the accommodation model that is practical, the achievable room configuration and the amount of capital required to complete the project.

That makes property selection particularly important.

An existing dwelling may offer strong conversion potential when its layout, services and site characteristics align with the intended use. INVIDA’s guide to adaptive reuse and property conversion explores how existing buildings can be repositioned when the underlying property is suitable.

In other circumstances, starting with a new design can provide greater control over room layouts, common areas, accessibility and building services. Investors considering this pathway can explore INVIDA’s custom-built co-living homes.

The appropriate approach depends on the property, jurisdiction, intended operating model and investment strategy.

Planning and building approvals can only be determined by the relevant authorities and qualified professionals after the project has been properly assessed. What investors can control is how early those issues are investigated.

INVIDA helps investors assess opportunities with those considerations in mind, coordinate the specialists needed throughout the project and identify potential constraints before significant capital is committed.

If you are considering a co-living conversion or new development in Queensland, New South Wales, Victoria or Western Australia, speaking with INVIDA during the feasibility stage can provide a clearer understanding of what the property may realistically support.

The earlier the property, design and approval pathway are considered together, the easier it becomes to make an informed investment decision.

Building Code Australia FAQs

1. What is the Building Code Australia and how does it apply to co-living?

The Building Code Australia forms part of the National Construction Code and sets technical requirements for buildings across Australia. For co-living projects, it can influence building classification, fire safety, accessibility, plumbing, exits, ventilation and other design requirements. The exact rules that apply depend on the property, its intended use and the state or territory where the project is located.

2. Does converting a normal house into co-living change its building classification?

It can. A conventional detached home is usually Class 1a, but a property converted for separate room-by-room accommodation may need to be assessed as Class 1b, Class 3 or another classification depending on its design and use. A qualified building certifier or building surveyor should confirm the classification before the layout and construction scope are finalised.

3. What is the difference between a Class 1b and Class 3 co-living property?

A Class 1b building can include a small boarding house, guest house, hostel or similar accommodation that ordinarily houses no more than 12 people and has no more than 300 square metres of total floor area. Larger shared-accommodation properties may fall within Class 3 and can face more extensive requirements for fire safety, access, exits and other building systems.

4. Do I need council approval to convert a property into co-living accommodation?

Possibly. Building approval and planning approval are separate considerations. Depending on the location and proposed use, the project may require development consent, a material change of use application, a planning permit or another council approval. State-specific rules may also apply, so investors should confirm the planning pathway for the individual property before starting work.

5. What upgrades may be required when converting an existing house to co-living?

The required upgrades depend on the property and classification, but they can include additional smoke alarms, evacuation lighting, accessibility changes, plumbing and drainage work, bathroom upgrades, fire-safety measures, electrical work and alterations to entrances or circulation areas. The most reliable way to understand the likely scope is to assess the existing property before the room configuration is locked in.

6. Should I check Building Code Australia compliance before buying a co-living investment property?

Yes. Early feasibility can help identify whether the intended number of rooms, resident capacity and operating model are realistically achievable. Building classification, planning controls, site constraints and required upgrades can all affect the construction budget and investment return. Reviewing these factors before committing to a property can reduce the risk of expensive redesigns or approval issues later.

Disclaimer: This guide provides general information only. Building, planning and operational requirements can change and may vary according to the property, local council, proposed use and project scope. Investors should obtain project-specific advice from appropriately qualified planners, building certifiers or surveyors, designers, legal advisers and relevant authorities.