Answer first: From 1 May 2026 the NSW Planning Portal BASIX tool expanded low-SHGC glazing choices for alterations and additions, removed roof-space exhaust options for new homes (NCC 2022 condensation alignment), and moved standards version 4.03 to 4.04. In-progress cases keep their existing version. Renovators still need a BASIX certificate when works are valued at $50,000 or more.
Author: giantA Pty Ltd · Updated 1 October 2026
What changed in the BASIX tool on 1 May 2026?
The Department’s Planning Portal news and release notes confirm that on 1 May 2026 a package of BASIX tool upgrades went live to expand functionality, increase flexibility and apply technical updates. Two practitioner-facing changes matter most for renovators and designers:
- Alterations and additions: more glazing options with low Solar Heat Gain Coefficient (SHGC) values in the Frame and glass type field.
- New homes (single and multi dwelling): bathroom, kitchen and laundry exhaust types no longer offer a roof ventilation option, aligning the tool with NCC 2022 condensation management requirements.
The same release upgraded the BASIX standards version from v4.03 to v4.04 for all application types, while stating that older and in-progress cases remain on the version they were created in. Certificates and reports for new homes now show the thermal performance method used, and multi-dwelling certificates can display photovoltaic (PV) panel group counts where applicable.
Primary sources: 1 May 2026 release summary · BASIX tool upgrades now live.
This guide is for designers and renovators working the alterations pathway — and for teams who must not confuse that pathway with new-home 7-star NatHERS-style targets. Sister posts cover the $50k trigger, why a certificate is still required over $50k, and when simulation/NatHERS is allowed for alterations.
Do alterations and additions valued at $50,000 still need a BASIX certificate?
Yes. The Planning Portal’s alterations and additions dwelling-type page states that BASIX applies to all alterations and additions in NSW that are valued at $50,000 and over and/or involve the installation of a pool and/or spa with a total volume greater than 40,000 litres. The BASIX hub page repeats the same renovation threshold: renovations of $50,000 or more require a BASIX certificate.
Do not use an outdated $25,000 figure. Always confirm the live Planning Portal wording before briefing clients or builders.
Sources: Alterations and additions — Planning Portal · BASIX — Planning Portal.
Related: pools/spas 40,000 L trigger · BASIX and NatHERS overview · BASIX assessment Sydney.
How is the alterations pathway different from new-homes BASIX?
This distinction is where renovation briefs often go wrong. The Planning Portal is explicit that the alterations and additions section of the tool differs from the single-dwelling and multi-dwelling sections: there are no set reductions for energy or water. Instead, the tool aims to reduce potential water consumption and emissions by encouraging efficiency improvements.
Published efficiency commitments for the alterations pathway include (paraphrased from the Portal):
- reducing heating and cooling energy through improved glazing, insulation, building design and construction materials
- requiring at least 40% of new or altered light fixtures to use high-efficiency globes
- promoting solar, gas, heat pump or wood systems instead of high-emission electric hot water
- requiring new taps, toilets and showerheads to meet a minimum efficiency rating of 3 WELS stars
- reducing pool and spa emissions by phasing out high-emission electric heating, and reducing pool/spa water use via rainwater tanks and covers
By contrast, new residential development is assessed against the BASIX standards for water, energy and thermal performance — including the higher standards that took effect from 1 October 2023 (commonly discussed with 7-star NatHERS-aligned thermal performance for new homes). Those percentage / star frameworks are not the same as the alterations efficiency-commitment pathway. Keep DA reports, client emails and builder mark-ups clear on which pathway applies.
| Topic | Alterations & additions | New homes (single / multi) |
|---|---|---|
| When BASIX is required | $50,000+ works and/or pool/spa >40,000 L | New residential development (Portal BASIX standards) |
| Energy / water targets | No fixed % reductions; efficiency commitments | BASIX standards (higher standards from 1 Oct 2023) |
| May 2026 glazing change | Expanded low-SHGC Frame and glass type options | Separate new-home glazing / thermal methods |
| May 2026 ventilation change | Not the headline alts change in the release notes | No roof-space exhaust option for bathroom/kitchen/laundry |
| Standards version after 1 May 2026 | v4.04 for new cases; older cases keep prior version | Same version rule |
Source for alterations pathway wording: Alterations and additions. For dual occupancy / multi-dwelling packaging see BASIX dual occupancy NSW 2026.
What do the new low-SHGC glazing options mean for renovators and designers?
The 1 May 2026 release summary states that applicants can select more glazing options with low Solar Heat Gain Coefficient (SHGC) values for the Frame and glass type field in an Alterations and Additions BASIX application. The “upgrades now live” news post summarises the same point as expanded glazing options with low SHGC values for alterations and additions.
Practical implications for design teams (without inventing product lists the Portal does not publish):
- Specify early. Window schedules and elevations should nominate frame/glass performance that can be selected in the live tool — not a generic “low-e” note that nobody can map to a Frame and glass type row.
- Coordinate with orientation. Low SHGC glazing is especially relevant on sun-exposed elevations in Sydney renovations; pair it with insulation and shading already contemplated in the alterations efficiency commitments.
- Keep evidence tidy. Store manufacturer SHGC/U-value data with the BASIX project file so the certificate selections match what is drawn and what the builder orders.
- Simulation still has its place. Where the Portal allows simulation for alterations, NatHERS modelling may still be the cleaner path for complex envelopes — see our simulation for alterations guide.
The release notes do not publish a closed catalogue of new glass codes here; always select from the live BASIX Frame and glass type list for the project version.
What ventilation changes apply to new homes after 1 May 2026?
For new homes (single dwelling and multi dwelling), applicants select ventilation system types for bathroom exhaust, kitchen exhaust and laundry exhaust without a roof ventilation option. The release summary states this aligns with NCC 2022 condensation management requirements. The upgrades-now-live article puts it plainly: there is no longer an option for directing exhaust into the roof space.
Design and documentation checklist:
- Show exhaust discharge to outdoors (for example façade or roof cowl to external air) on plans and sections — not into roof space.
- Coordinate with the builder’s wet-area and rangehood package before the BASIX certificate is locked.
- Remember this ventilation tool change is described for new homes in the May release notes; do not assume the same wording applies to every alterations case without checking the live tool for that application type.
Deeper ventilation context: BASIX ventilation changes 2026.
What does the version upgrade from 4.03 to 4.04 mean for open projects?
The release summary states an upgrade from version 4.03 to 4.04 for all BASIX application types, and that applicants can accommodate the version upgrade without affecting older cases — previous cases remain in the version they were created in. The upgrades-now-live article adds that in-progress projects will not be affected by the standards version change in the way new work is.
Separately, the release notes confirm that for all BASIX application types, applications already in progress can proceed without impacting the expected dropdown values and calculation scores carried over from older versions of the service.
Workflow tip: when you revise a certificate after design change, confirm whether you are revising within the original version or starting a fresh case under v4.04. Validity and revision timing still matter — see BASIX certificate validity NSW 2026.
What other May 2026 upgrades should designers verify on the live tool?
These items appear in the official 1 May 2026 release summary and/or the upgrades-now-live news post. Use them as a verification list — not as a substitute for the live Portal:
| Upgrade | Applies to | Why designers care |
|---|---|---|
| Data retained when switching DIY / Simulation / Passive House thermal methods | New homes (single + multi) | Fewer re-keying errors when the assessment method changes mid-project |
| Thermal performance method shown on certificate/report first page | New homes | Clearer audit trail for DA / CC packages |
| PV panel groups displayed on certificate/report | New homes multi-dwelling (excl. revised certificates per release notes) | Multi-dwelling energy schedules easier to check |
| Up to 1,000 dwellings on one multi-dwelling certificate (request pathway) | Multi-dwelling | Useful for large staged residential — confirm help text and administrator limits |
| Clearer materials guidance for separate buildings with shared common areas (‘Unit and other buildings – All’) | Multi-dwelling (excl. revised certificates) | Materials Index entries less ambiguous for shared amenities buildings |
| Low-emissions concrete grades for internal walls | New homes | More granular embodied-emissions selections |
| Green Square Town Centre reticulated alternative water (postcode 2015) | Single + multi new homes | Site-specific water supply option where address matches |
| Showerheads 4.5–6 L/min shown as 5 stars | Single + multi (per release notes) | Fixture schedules should match the live WELS mapping |
| Compulsory accuracy declaration before generating a certificate | All application types | NatHERS assessor and designer data must be true and correct |
Providing incorrect or false information is described by the Department as a breach of the BASIX Terms and Conditions that may result in compliance action. Treat certificate generation as a formal declaration, not a draft checkbox.
How should renovators sequence design, BASIX and lodgement after the May upgrades?
- Confirm the trigger — $50,000+ alterations/additions and/or pool/spa >40,000 L (Portal wording).
- Freeze the envelope enough to select glazing — use the expanded low-SHGC Frame and glass type options where they suit the design.
- Choose the correct pathway — alterations efficiency commitments versus new-homes standards; do not paste 7-star language into a renovation certificate narrative.
- Coordinate wet areas for new homes — exhaust not to roof space; match plans to selectable exhaust types.
- Generate under the correct version — new cases under v4.04; leave genuine in-progress cases on their original version unless a deliberate restart is required.
- Lodge within validity — keep certificate, drawings and application aligned; revise when design changes.
- Declare accuracy — tick the compulsory confirmation with evidence on file.
Pathway pages: /basix-and-nathers · /basix-assessment-sydney · /help · /architectural-services.
Frequently asked questions
Is the BASIX alterations threshold still $50,000 after the May 2026 tool upgrades?
Yes. The Planning Portal alterations page and BASIX hub still state that renovations / alterations and additions valued at $50,000 and over require a BASIX certificate (and/or pool/spa greater than 40,000 litres). The May 2026 release expanded tool options; it did not replace that threshold with $25,000.
Do alterations and additions have the same energy and water percentage targets as new homes?
No. The Portal states the alterations section has no set reductions for energy or water. It encourages efficiency improvements through commitments (glazing, lighting, hot water, WELS fixtures, pool/spa measures). New homes are assessed against the BASIX standards, including higher standards from 1 October 2023.
What is the main glazing change for alterations in May 2026?
Applicants can select more glazing options with low SHGC values in the Frame and glass type field for Alterations and Additions applications. Confirm available rows in the live tool for your certificate version.
Can new-home bathroom exhaust still discharge into the roof space?
Not via the BASIX tool options described in the May 2026 release: bathroom, kitchen and laundry exhaust types are available without a roof ventilation option, aligning with NCC 2022 condensation management. Design exhaust to external air and match the selectable types.
Will my in-progress BASIX case jump to version 4.04 automatically?
The Department states previous cases remain in the version they were created in, and in-progress projects can proceed without impacting expected dropdown values and calculation scores from older versions. New work reflects v4.04. Verify on the live project before regenerating.
Where can I read the official May 2026 notes?
Start with the 1 May 2026 release summary and BASIX tool upgrades now live on planningportal.nsw.gov.au, then open the live BASIX tool for the project type you are lodging.
Can giantA help with a renovation BASIX package?
Yes — for design-led renovations and additions that need a coordinated BASIX certificate with drawings. Start via Help or read BASIX assessment Sydney. We do not invent fees or turnaround times in this article; ask for a scoped brief.
Key takeaways for renovators and designers
- $50,000+ alterations/additions (and/or pool/spa >40,000 L) still need BASIX — cite the Planning Portal, not folklore.
- Alterations = efficiency commitments, not new-home percentage / 7-star targets.
- May 2026: more low-SHGC glazing options for alterations; no roof-space exhaust option for new-home wet areas; version 4.04 for new cases.
- Keep certificate, drawings and fixture schedules aligned — and use the compulsory accuracy declaration seriously.
Sources cited throughout: NSW Planning Portal release summary (1 May 2026), BASIX tool upgrades now live, alterations and additions dwelling types, and the BASIX hub page on planningportal.nsw.gov.au.