Meet your Spatial Daylight Autonomy, BESS IEQ, Green Star daylight compliance targets, or indoor environment quality best practice.
A JV3 assessment, formally J1V3 under NCC Section J, models your whole building against a reference building. For Melbourne and Victorian projects, it finds a compliant path before you pay for upgraded glass, not after the tender comes back.
Request a Fee Proposal →Send us your drawings and project address. We'll tell you whether JV3 is worth it, and confirm scope and fee before you commit.
Deemed-to-Satisfy checks each element in isolation. A building with excellent roof insulation can still fail because one facade has too much glass. J1V3 compares the proposed building with a reference building. It must meet a greenhouse gas emissions target and other tests, and the envelope must stand on its own without help from HVAC or lighting. Often the design can stay intact.
A west-facing curtain wall can fail the DTS glazing calculation on its own. Whole-building modelling can show that better roof insulation, shading or other envelope elements make up the difference. Under NCC 2025, gains in HVAC or lighting cannot offset a weaker envelope.
Meeting DTS with high-performance glazing and thermally broken frames adds real cost. JV3 can often show compliance with a simpler specification by trading performance across the building.
Victoria adopted NCC 2025 from 1 May 2026. Section J is more stringent for Class 3 and 5–9 buildings, and the Deemed-to-Satisfy Provisions of Part J9 (J9D5) now require on-site solar PV in most cases. Earlier DTS assumptions may no longer pass.
J1V3, commonly called JV3, is a Verification Method in NCC Section J used to support a Performance Solution. Instead of meeting each Deemed-to-Satisfy requirement element by element, the whole building is modelled and compared with a reference building of the same form. Under NCC 2025, the proposed building's modelled greenhouse gas emissions must be no more than 97% of the reference building's. It must also meet the thermal comfort or heating and cooling load test and other conditions. Your building surveyor decides whether the Performance Solution complies.
It applies to commercial and mixed-use buildings, including hotels, offices, retail, warehouses, hospitals and aged care. Design teams choose it when DTS forces expensive upgrades, when non-standard geometry doesn't fit the DTS calculations, or when they want to trade performance between elements. NCC 2019 called it JV3; NCC 2022 renamed it J1V3.
The result is a signed modelling report for your building surveyor's assessment. It documents the simulation method, input assumptions and compliance outcome. Not sure you need modelling yet? Start with a Section J report: if DTS passes, you won't need JV3.
A Verification Method used to support a Performance Solution under NCC Section J. Your building is modelled as a whole system and compared with a reference building of identical form. Used when DTS can't be satisfied, or when trading performance across elements reduces construction cost.
Get a clear picture of where your building has performance headroom and where it has performance gaps. Glazing specification, window to wall ratio, shading strategies, insulation options and HVAC efficiency — recommendations you can act on while changes are still cheap.
A JV3 report from Makao shows more than compliance. It shows how far the proposed building sits from the reference building, which elements carry the result and which drag it down. If the design doesn't pass, we model a revised option and report both in the same document.
Modelled annual performance of your design against the NCC reference building, with the compliance margin stated clearly.
Where the performance comes from: envelope, glazing, HVAC and lighting. Shows the design team which levers matter most.
Where the first run fails, we test practical changes, such as shading, glazing or roof insulation, and report the compliant option.
A signed J1V3 report with method, inputs, assumptions and outcome, structured for your building surveyor or council.
JV3 gets triggered at different stages for different reasons. These are the situations we see most often on Melbourne and Victorian projects.
Glazing shortfall — the most common JV3 trigger. We model the whole building to find whether gains elsewhere in the envelope, such as the roof, walls or shading, can offset the glazing shortfall without changing the design intent.
Surveyor request — some building surveyors ask for J1V3 when DTS can't be satisfied or the design is too complex for elemental checks. We deliver a surveyor-ready report with a clear method and compliance evidence.
Glazing cost — DTS-compliant glazing, with thermally broken frames, low-E coatings and argon-filled IGUs, adds real cost. JV3 modelling can often demonstrate compliance with simpler, less expensive glass by trading performance across the whole building.
Heritage constraints — heritage fabric and DTS rarely coexist. JV3 lets us model the building as it is and show whether other envelope elements, such as an upgraded roof or improved glazing, compensate for the existing fabric. HVAC and lighting upgrades reduce energy use but cannot offset the envelope under NCC 2025.
Late engagement — late, but not too late. We prioritise the modelling and identify whether the current design passes, or the minimum changes needed to get there before construction starts.
Non-standard systems — innovative cladding, phase-change materials or unconventional HVAC configurations don't map to DTS lookup tables. JV3 modelling demonstrates compliance from modelled performance rather than prescribed specifications.
Multi-building projects — mixed-use precincts benefit from a unified JV3 approach. We model each building consistently, identify where headroom exists across the project, and streamline the compliance pathway.
"We’re designing to exceed code and want to quantify how much better than minimum our building actually performs."
Beyond code — JV3 doesn't just show whether the design meets the target, it shows by how much. For projects targeting Green Star Buildings, NABERS or simply a better building, it gives a measurable benchmark against the NCC baseline.
Architectural drawings, site location and any preliminary services information. We confirm scope, fee and turnaround before you commit.
We build a detailed 3D thermal model of your design, with your geometry, materials and HVAC system, and create the NCC reference building for comparison.
Good envelope insulation? Efficient glazing systems? Favourable orientation? We use those gains to offset areas where DTS says you cannot optimise.
A signed J1V3 report ready for your building surveyor or council submission. It includes the modelling method, assumptions and compliance outcome.
A JV3 assessment (J1V3 since NCC 2022) is the Section J verification method that compares a proposed building's modelled performance with a reference building of identical form. Under NCC 2025, the proposed building's modelled greenhouse gas emissions must be no more than 97% of the reference building's. It must also meet the thermal comfort or heating and cooling load test and other conditions. Your building surveyor decides whether the Performance Solution complies. It's used when Deemed-to-Satisfy would force costly upgrades or can't accommodate the design.
Yes. NCC 2019 called the method JV3. NCC 2022 restructured Section J and renamed it J1V3, verification using a reference building. Most of the industry still says JV3. Both terms refer to the same whole-building modelling pathway.
When a DTS check shows the design is close but failing on one or two elements, usually glazing. Also when the facade has high window-to-wall ratios, non-standard geometry or heritage fabric, or when better roof or wall insulation could offset glazing. We'll tell you honestly whether JV3 is likely to pay for itself.
Victoria adopted NCC 2025 from 1 May 2026. For Class 3 and 5–9 buildings, Section J is more stringent, so the reference building is harder to beat, and the Deemed-to-Satisfy Provisions of Part J9 (J9D5) now require on-site solar PV in most cases. Projects assessed under NCC 2025 should be modelled against the NCC 2025 provisions.
Yes, the assessment fee is higher because the modelling takes more work than a DTS check. The relevant comparison is total project cost. If JV3 avoids upgraded glazing or facade changes, the extra fee can be recovered many times over. We'll tell you whether the likely savings justify it before you commit.
Architectural drawings at design development (floor plans, elevations and sections) and the site address. A preliminary services schedule helps, but we can start with stated assumptions and refine them. The earlier we're involved, the more options we have to influence the outcome.
We also prepare DTS Section J reports, so if DTS passes, we say so. JV3 is recommended only when it pays for itself.
Models are prepared against the NCC edition that applies to your permit, including NCC 2025 in Victoria from 1 May 2026.
Preliminary runs during design development, so glazing and services decisions are made with compliance data, not after it.
J1V3 models can often be extended for Green Star Buildings work, so the building is only modelled once.
Signed reports that set out method, inputs, assumptions and outcome in the order a building surveyor checks them.
Local knowledge of Victorian building surveyors, councils and the facade systems common on Melbourne projects.
