Which rules apply to this building

The first question on any building project is not technical. It is which set of rules you are being judged against. A factory owner who reads the wrong edition of the code, or a national clause that their state has varied, can do every calculation correctly and still be wrong.

This chapter sets up the legal and documentary frame for the rest of the book. It explains where the National Construction Code (NCC) gets its force, how editions and state variations work, how the code is structured, and what the running case project looks like before any design decisions are made.

Building law comes from the states

The NCC is written and maintained by the Australian Building Codes Board, a joint body of the Commonwealth, state and territory governments. On its own, it has no legal force. Each state and territory gives it force through its own building legislation, and that legislation decides which edition applies, when it starts, who may approve building work and what records must be kept.

That arrangement has three practical consequences:

1. The edition depends on the state and the date. NCC editions are published on a cycle, and each jurisdiction adopts a new edition on its own timetable.
2. The national text is not the whole text. States and territories add, remove or replace clauses. NCC Online shows many of these variations alongside the national clause, flagged by state.
3. Approvals are a state process. The NCC sets technical requirements. Who checks them, when inspections happen and what certificates are issued come from state law.

Planning law sits alongside building law and is a separate system. A planning or development approval decides whether a use is permitted on the land and sets conditions such as hours, parking, landscaping and bushfire or flood controls. A building approval decides whether the construction meets the building code. A factory project usually needs both, and planning conditions can affect building design.

Which edition, and which version

As of late 2026, two editions are in use across Australia. NCC 2022 remains in force where a state has not yet adopted NCC 2025. NCC 2025 is available for adoption from 1 May 2026, and the ABCB publishes each jurisdiction’s adoption information. NSW has announced that it will adopt NCC 2025 from 1 May 2027, with a transition period.

Editions can also be amended between full releases. NCC 2022 has an amendment, and the ABCB lists the standards that form part of each edition. When someone says “the NCC”, always ask which edition, which amendment and which state’s version.

State law also sets the transition rules: whether the edition is fixed by the date an application is lodged, the date it is approved or some other trigger. Ask the certifier to confirm the edition in writing at the start. It is one sentence in an email and it removes a whole class of argument.

Figure 1Settling the rule set before design starts

The which edition of a standard applies chapter covers the same problem for referenced standards. The NCC fixes the edition of each standard it calls up. A newer edition of an Australian Standard on the shelf is not automatically the one that counts.

How the code is organised

The NCC has three volumes. Volume One covers Class 2 to 9 buildings, which includes offices, shops, warehouses, factories, health care and public buildings, and some Class 10 structures. Volume Two covers houses and their sheds and garages. Volume Three is the Plumbing Code of Australia. A factory with an office sits in Volume One.

Volume One is divided into Sections, Parts and clauses. Section A holds the Governing Requirements: how to interpret the code, how to comply, how states vary it, referenced documents, evidence of suitability and building classification. The technical Sections follow: B for structure, C for fire resistance, D for access and egress, E for services and equipment, F for health and amenity, G for ancillary provisions, I for special use buildings and J for energy efficiency.

Clause numbers in NCC 2022 tell you what kind of provision you are reading. The middle letter is the key:

Figure 2Reading an NCC 2022 clause number

Two ways to comply

The NCC is a performance-based code. Under A2G1, a building complies if it meets the Governing Requirements and the Performance Requirements. The Performance Requirements are written as outcomes: exits must allow occupants to evacuate safely, for example, with their number and dimensions appropriate to the travel distance, the number and mobility of occupants, the use of the building and its height.

You can meet a Performance Requirement in two ways, or a mix of both (A2G1 and A2G4):

• A Deemed-to-Satisfy (DTS) Solution. You follow the prescriptive DTS Provisions, which are deemed to meet the Performance Requirements. These are the clauses with numbers and tables: travel distances in metres, fire compartment areas in square metres, fixtures per number of workers.
• A Performance Solution. You show by another route that the relevant Performance Requirements are met, or that your design is at least equivalent to the DTS Provisions. A2G2 lists the Assessment Methods and the steps that a Performance Solution must follow.

Most industrial projects are mostly DTS, with perhaps one or two Performance Solutions where the DTS answer does not suit the building. This book works mainly through the DTS Provisions, because they are where owners can check the numbers themselves. Chapter 10 returns to Performance Solutions and the evidence they need.

A short history of the performance-based code

The structure you see in NCC 2022 is not new. The supplied 2004 edition of the Building Code of Australia (BCA 2004) already describes both of its volumes as drafted in a performance format, so that new products, systems and designs could be used. It shows a pyramid of Objectives and Functional Statements as guidance, with Performance Requirements as the compliance level and two kinds of Building Solution below them: the Deemed-to-Satisfy Provisions and “Alternative Solutions”.

The four Assessment Methods in BCA 2004 were documentary evidence, Verification Methods, comparison with the DTS Provisions and Expert Judgement. NCC 2022 lists the same four in A2G2(2), in a different order. What has changed is the vocabulary and the discipline around it. “Alternative Solution” has become “Performance Solution”. NCC 2022 also sets out a required process: a performance-based design brief, analysis, evaluation against agreed acceptance criteria, and a final report. Plumbing has joined the code as Volume Three, and clause numbering was rebuilt in 2022.

Figure 3From BCA 2004 to the editions in use today

The history matters for one practical reason. Buildings outlive code editions. An industrial building approved under an older code may contain features that were compliant then and are not under the current DTS Provisions. Unless state law requires an upgrade, existing work is generally assessed against the rules it was approved under, and new work against the current rules. When you alter a building, ask the certifier which parts of the existing building the new work will pull into the current code.

The running case before any design decisions

This is an illustration. A precision-engineering business has bought a single-storey steel portal-frame building on a regional NSW industrial estate. The facts that matter for the code are:

• Footprint: 60 m by 30 m, so 1,800 m² on one level, on a concrete slab.
• Height: 6.0 m at the eaves and 7.5 m at the ridge, with the ridge running the length of the building.
• Proposed use: a 300 m² office at the east end, facing the road, and a 1,500 m² workshop. The workshop holds a 600 m² machine shop, an 840 m² fabrication and assembly area, and 60 m² of amenities and circulation.
• Mezzanine: the owner’s first sketch shows a 240 m² storage mezzanine in the workshop with its deck 3.0 m above the floor.
• Location: a regional town with a fire station 4 km away by road.
• People: on the busiest shift the owner expects about 30 people in the workshop and 12 in the office.

The building was approved years ago as an empty warehouse. The new work is a change of use, an office fit-out and a mezzanine, so it needs new approval. Under NSW law in 2026, the technical standard is NCC 2022.

Figure 4The running case before design decisions

What the building code does not decide

The NCC is about the building: its structure, fire safety, egress, amenity, accessibility and energy use. Many of the rules that shape a factory sit elsewhere, and a building approval does not confirm compliance with them.

• Work health and safety law governs how the workplace is run: machine guarding, plant registration, hazardous chemicals, noise, manual handling and emergency plans. An approved building can still be an unsafe workplace.
• Dangerous goods and hazardous chemicals rules may limit how much flammable liquid or gas you store and where. Those quantities can also feed back into building requirements, as Chapter 7 shows for fire extinguishers.
• Electrical, gas and plumbing work has its own licensing and installation rules. The NCC’s Volume Three covers plumbing; electrical installation rules sit outside the NCC.
• Planning conditions may cap hours, noise, vehicle movements or the number of workers.
• Lease and insurance terms may demand more than the code, such as sprinklers an insurer requires even where the DTS Provisions do not.

A good project file lists these regimes next to the building code, with an owner for each. The owner of the business usually holds the WHS duties; the designer and certifier deal with the building code; specialists handle the rest.

Who does what on an industrial project

The roles vary by state, but the pattern is similar. The owner decides what the building is for and pays for the work. A designer, often an architect or building designer, prepares drawings and coordinates engineers. Structural, fire, hydraulic, mechanical and electrical engineers design their systems. A registered building certifier (in NSW, a registered certifier appointed as principal certifier) assesses the design against the code, issues the approvals the state requires, inspects the work at set stages and issues the certificate that allows occupation. The builder builds to the approved documents.

The owner’s job in this chain is often underestimated. Only the owner can say how many people will work in the building, what will be stored and how high, which processes use flammable liquids and how the business may grow. Every one of those facts changes a code answer. When the designer or certifier asks, the answer should be a considered number, recorded and kept with the drawings.

Where owners go wrong at this stage

The common error is not getting a clause wrong. It is starting work on the wrong basis. Three versions are typical.

Reading a generic summary instead of the code. Industry summaries, supplier brochures and old project files are useful pointers, but they drift from the text. In the running case, the owner’s estimator used a building-code summary from a previous project in another state. It quoted an exit travel distance concession that the NSW-adopted text does not contain for this building class. The error was caught when the estimator was asked to cite the clause and could not find it on NCC Online.

Assuming the old approval covers the new use. A building approved as a warehouse was checked against storage occupant numbers, storage fire risks and storage amenities. A machine shop puts far more people per square metre into the same floor (Chapter 5) and changes the fire equipment and amenities required. A change of use is a new question.

Leaving the certifier out until the design is finished. The certifier cannot design your building, but they can confirm the edition, the classification and how they will read ambiguous clauses. An early meeting with sketch plans is cheap. A late redesign is not.

Figure 5Rule-set record for the running case

Exercise: settle the rule set

A second owner plans a similar fit-out in a state that adopted NCC 2025 on 1 May 2026. Their designer has worked from NCC 2022 because “that is what we used last year”. What should the owner do, and what record should they keep?

Worked answer. First, find out which edition actually applies. The ABCB’s adoption page and the state’s building regulator will show the adoption date and any transition rules, and the certifier should confirm the edition in writing. If NCC 2025 applies, the designer must check every clause relied on against the NCC 2025 text, including clause numbers, values and state variations. NCC 2025 may differ from NCC 2022 in places that matter to the design, so “it was the same last year” is not evidence.

The record should state the jurisdiction, edition, version, the date and basis of the decision (for example, “application lodged after the adoption date”), the certifier’s written confirmation, and a list of the referenced standards and their editions as called up by that NCC edition. Keep it at the front of the compliance file so that every later calculation can be traced to the right text.