INSIGHT · MATERIALS & COMPLIANCE
The score is information only.
The material you named is a commitment.
New residential development in NSW has had to report embodied emissions through the BASIX Materials Index since 1 October 2023. The department's Embodied Emissions Technical Note (March 2026) states there is currently no target and the score is provided for information only. The same sentence states that the materials selected are included as commitments on the BASIX certificate, which the certifying authority will check at development application, construction certificate and occupation certificate stage. The score is not measured against anything. The selections are.
Analysed 28 September 2026 · NSW Embodied Emissions Technical Note, March 2026 revision, the version linked from the Sustainable Buildings SEPP page updated 2 July 2026 · BASIX FAQ (currency statement March 2023) · NSW Planning Portal BASIX page (no date shown) · ABCB handbook news item published 22 July 2026 · all pages read 28 September 2026.
Key takeaways
- Reporting applies to all new residential development: The technical note states: "All new residential and non-residential developments must report on embodied emissions under the SB SEPP." The BASIX FAQ states that BASIX assessments include the materials index from 1 October 2023 and that it applies to all new residential buildings across NSW.
- There is currently no target: In the technical note's words, "there is currently no target for the BASIX Materials Index and the score is provided for information only". The department states the data "will inform benchmarks and future targets".
- The selections are commitments, checked three times: The same sentence continues: "the materials selected are included as commitments on the BASIX certificate". The certifying authority will check the emissions reporting and commitments at the development application (DA), construction certificate (CC) and occupation certificate (OC) stage.
- The inputs are selections, not quantities: For residential work, the applicant enters the size of the development and selects what the floors, walls, ceiling, roof and glazing are constructed from. The BASIX calculator derives the volumes.
- We would version the materials schedule against the certificate: Our system-design recommendation: hold what each covered element is made of at DA, at CC and as built, with the date and reason for every change, so a business can show whether the building still matches what the certificate records.
What the requirement is
The State Environmental Planning Policy (Sustainable Buildings) 2022, the SB SEPP, requires embodied emissions measurement and reporting across building types. For residential development the mechanism is a Materials Index inside the Building Sustainability Index (BASIX) online tool. Applicants "are required to disclose the quantities of key materials and associated embodied emissions at the development application (DA) and construction certificate (CC) stages, or when applying for a residential complying development certificate (CDC)".
- Upfront emissions only: The note describes the target of reporting as "upfront embodied emissions, often referred to as 'cradle-to-gate' emissions or stages A1-A3 of a building's life cycle": the emissions of manufacturing a product. It states that the SB SEPP "does not require reporting on the full life cycle impacts of building materials".
- Structure and envelope, not fit-out: The Materials Index assesses "the entire residential building, including dwellings and common areas". Components include floors, walls (external and internal), ceilings, roof and glazing. Emissions from "the building site, interior finishes, fit-outs and services are excluded from reporting".
- A stated purpose: "Reporting embodied emissions will enable important data to be captured on quantities of key materials and construction practices. This will inform benchmarks and future targets."
How the residential number is made
The residential calculation runs in one direction, and the direction decides what has to be kept. The applicant does not enter a bill of quantities. The technical note describes the steps below.
Steps 2, 4 and 5 are calculated from what is entered at step 1, so the size data and construction types entered for each element are what would need to be kept to reproduce the calculation later.
| Step | As the technical note describes it |
|---|---|
| 1. Selections | Applicants "enter data on the size of the development and select what materials the floors, walls, ceiling, roof and glazing are to be constructed from". |
| 2. Volumes and quantities | "The BASIX calculator then determines the volume of each construction type to determine the quantities of materials and their associated embodied emissions." |
| 3. Emission factors | Default factors come from the Environmental Performance in Construction (EPiC) database. A material not in the index can go through the BASIX alternative assessment process. |
| 4. Per capita | Total emissions are "divided by the assumed number of occupants", derived in line with the NatHERS whole-of-home occupancy calculations. |
| 5. Score | The per capita value is compared with an average for the development type "to produce a score showing the percentage reduction of emissions compared to the average". |
One sentence,
two directions.
The first half is why the requirement is easy to file as reporting with no consequence. The second half attaches the inputs to a certificate that is checked at three points. A BASIX certificate already carried water, energy and thermal commitments. With the Materials Index, the technical note states, it also carries the materials selected for the floors, walls, ceilings, roof and glazing.
While there is currently no target for the BASIX Materials Index and the score is provided for information only, the materials selected are included as commitments on the BASIX certificate. The certifying authority will check the emissions reporting and commitments from the Materials Index on a BASIX certificate at the development application, construction certificate and occupation certificate stage.
- At development application: The selections are a design intention.
- At construction certificate: They are a documented intention, usually tied to a set of construction drawings.
- At occupation certificate: They are a statement about a building that now exists. This is the check point that can be compared against what was actually installed.
Where the materials change
Materials in a residential building can change between construction certificate and occupation certificate for reasons unrelated to emissions: price, lead time, availability, or a supplier who cannot deliver the specified product in the window the programme needs. A change to an external wall system or a glazing system made in month seven is an ordinary procurement decision. It is also a change to an element whose construction type the BASIX certificate records as a commitment.
- Two records, two owners: The substitution is recorded in a procurement log, a request for information or a variation. The BASIX certificate is a separate document, generated earlier.
- What we have not established: The technical note says the certifying authority will check the commitments. It does not describe what that check consists of or what happens on a mismatch, and we found no primary source that does.
Two evidence regimes, one business
There is no single national position on embodied carbon, and the regimes a business meets differ in method, not only in degree.
The ABCB's embodied carbon handbook, announced on 22 July 2026, covers Class 2 common areas, Class 3 buildings and Class 5 to 9 buildings, and the ABCB states it "is voluntary guidance and does not introduce new NCC requirements, compliance obligations or mandatory provisions". We read the ABCB's news item, not the handbook.
| Regime | How quantities are established | Status |
|---|---|---|
| NSW residential (BASIX Materials Index) | Construction-type selections; the calculator derives volumes | Reporting required; "currently no target"; selections are certificate commitments |
| NSW non-residential (contrast only) | "an itemised list of building materials (e.g. a bill of quantities) prepared by a quantity surveyor"; "At least 80% of materials by quantity must be accounted for" | Form certified by "a quantity surveyor, qualified designer, engineer, or NABERS assessor" and uploaded at DA and CC |
| National Construction Code (NCC) | No method required | The Australian Building Codes Board (ABCB) states the NCC "does not currently contain any requirements, provisions or compliance obligations relating to embodied carbon" |
What we would put in a system
The useful output is small. For each residential project with a BASIX certificate, we would hold four fields.
Where agents help is narrow. A document intelligence agent can read a BASIX certificate, extract the committed construction types, compare them with the current materials schedule and draft an exception list; a person reviews every exception and decides what it means. No agent determines whether a development meets its commitments, whether a substitution is acceptable or what a certifier will accept, and no agent submits anything. Those are matters for the certifier, the consent authority and your advisers.
| Field | Why it is load-bearing |
|---|---|
| Committed construction type per element | Floors, walls, ceilings, roof and glazing as entered in the Materials Index, with the certificate number and date. |
| Current construction type per element, versioned | What each element is made of at DA, at CC and as built, with the date and reason for each change. This is design data, not a sustainability file. |
| Substitution flag | Set on any procurement change to a covered element, so a substitution raises the certificate question at the moment it is decided rather than at occupation certificate stage. |
| Source and read-date of the method | Which revision of the technical note the project was assessed under, and when it was read. The note has already been revised since the 2023 commencement. |
- Design Data & BIM: Where the versioned construction type for each element should live.
- Procurement: Where a substitution is decided, and where the certificate flag belongs.
- Document intelligence: Reads the certificate and drafts the exception list; a person confirms.
- Two registers, one standard edition: A companion reading on recording which edition of a referenced standard a product document relies on.
Questions worth asking
of your own records
For a developer: for a completed residential project, can you produce the construction types committed on the BASIX certificate alongside what each element was built from?
The technical note states the materials selected are included as commitments on the certificate. Comparing them with the building as built needs a record of what each covered element is made of as built.
For a builder: when an external wall or glazing system is substituted after the construction certificate, who checks it against the BASIX certificate?
If the answer is nobody until occupation certificate stage, the substitution and the commitment are being reconciled at the latest possible point, by someone who did not make the substitution.
For a design consultant: which revision of the Embodied Emissions Technical Note was current when each certificate was prepared?
The note in circulation today is the March 2026 revision. A record that stores the method with its revision date can be re-read later; one that stores only a score cannot.
For a building-product manufacturer: which emission factors are your customers' numbers built on?
Residential BASIX uses default factors from the EPiC database, with an alternative assessment route for materials not in the index. The non-residential form uses the NABERS calculator's inbuilt factors or a product-specific factor where one is available. The same product can be represented differently in each.
For a group running NSW and interstate work: which of your projects carry an embodied emissions commitment at all?
In NSW, BASIX assessments have included the Materials Index since 1 October 2023, and the technical note states the selections are included as commitments on the certificate. Nationally, the ABCB states the NCC contains no embodied carbon obligation. A single field that says which regime applied to each project answers the question directly.
What this analysis
does and does not show.
Evidence note
- What it shows
- That the NSW Materials Index score is currently information only, while the materials selected are recorded as commitments on the BASIX certificate and checked at DA, CC and OC stage; that the residential inputs are construction-type selections from which the calculator derives quantities; and that the NCC currently contains no embodied carbon obligation. As read on 28 September 2026 from NSW Department of Planning, Housing and Infrastructure, NSW Planning Portal and ABCB pages.
- Key facts quoted
- Reporting required for all new residential and non-residential development; materials index in BASIX assessments from 1 October 2023; "currently no target" and "for information only"; selections "included as commitments on the BASIX certificate"; checks at DA, CC and OC stage; stages A1-A3; floors, walls, ceilings, roof and glazing; non-residential at least 80% of materials by quantity (contrast only); ABCB handbook announced 22 July 2026 as voluntary guidance.
- We read the department's guidance, not the instrument. Where guidance and instrument differ, the instrument governs.
- Both NSW PDFs sit under a 2023-09 web path. The technical note's footer reads "March 2026" and it is the file linked from the Sustainable Buildings SEPP page (updated 2 July 2026) on 28 September 2026. The BASIX FAQ states it reflects understanding "at the time of writing, March 2023" and is used only for the 1 October 2023 commencement.
- "No target" is the department's present-tense statement, sourced to the word "currently".
- We did not find a primary source describing what the certifying authority's check consists of, what evidence is requested or what follows a mismatch.
- The ABCB handbook's publication date is 22 July 2026 on the ABCB news item and appeared as 15 July 2026 in one secondary summary we encountered while scanning. We use the publisher's date and have not resolved the difference. We did not read the handbook itself.
- This covers NSW only. Nothing here is legal advice, and it does not determine whether any development meets its BASIX commitments.
Bring us one BASIX certificate and its materials schedule.
Send us the certificate and the final materials schedule for the same building. We will show you where the two differ, if they do, and what a record that kept them together would have looked like.
This article is general information about published NSW planning guidance. It is not legal advice, it does not determine whether any development meets its BASIX commitments, and Cyberate does not prepare, issue or assess BASIX certificates. It describes NSW only. All quotations are as read on 28 September 2026 from the sources listed.
Sources
Suggested citation: NSW Department of Planning, Housing and Infrastructure, Embodied Emissions Technical Note (March 2026), and ABCB, Understanding embodied carbon: new handbook for practitioners (22 July 2026), as read 28 September 2026. Derived figures: none.
- NSW Department of Planning, Housing and Infrastructure - Embodied Emissions Technical Note: March 2026 revision (footer) · read 28 September 2026 · Government planning department - methodology note (PDF)
- NSW Department of Planning, Housing and Infrastructure - Sustainable Buildings SEPP: Updated 2 July 2026 · read 28 September 2026 · Government planning department - policy page linking the technical note
- NSW Department of Planning and Environment - Residential building sustainability (BASIX) frequently asked questions: Currency statement March 2023 · read 28 September 2026 · Government planning department - explanatory material (PDF)
- NSW Planning Portal - BASIX: No date shown · read 28 September 2026 · Government planning portal - scheme page
- ABCB - Understanding embodied carbon: new handbook for practitioners: Published 22 July 2026 · read 28 September 2026 · Government code administrator - news item