Meet your Spatial Daylight Autonomy, BESS IEQ, Green Star daylight compliance targets, or indoor environment quality best practice.
DTS compliance forces glazing and insulation specs that don’t suit every design. J1V3 — commonly referred to as JV3 — tests your whole building as a system, trading prescriptive rigidity for performance-based proof. Same code. Smarter path.
Get a quote →Send us your plans. We'll confirm scope, cost, and turnaround within 24 hours.
J1V3, commonly referred to as JV3, is a performance-based verification method under NCC Section J. Instead of meeting prescriptive Deemed-to-Satisfy requirements element by element, the entire building is modelled as a system and benchmarked against a code-compliant reference building of identical form. If the proposed design performs as well or better, it passes.
This pathway applies to commercial and mixed-use buildings (NCC Classes 3 through 9) covering hotels, offices, retail, warehouses, hospitals, and aged care facilities. It’s the route design teams choose when prescriptive DTS rules force expensive upgrades, when non-standard geometry doesn’t fit the lookup tables, or when the team wants flexibility to trade performance across building elements rather than satisfying each one in isolation.
The result is a signed modelling report that councils and building certifiers can rely on. It documents the simulation methodology, input assumptions, and energy efficiency outcome.
The performance-based pathway under NCC Section J. Your building is modelled as a whole system and benchmarked against a DTS-compliant reference building of identical form. Used when prescriptive 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, HVAC offsets — recommendations you can act on while changes are still cheap.
JV3 gets triggered at different stages for different reasons. These are the situations we see most often.
The most common JV3 trigger. We model the whole building to find whether gains elsewhere (roof, HVAC, orientation) can offset the glazing shortfall without changing the design intent.
Some certifiers require JV3 when the DTS pathway can’t be satisfied or when the design is too complex for elemental checks. We deliver a certifier-ready report with clear methodology and compliance evidence.
DTS-compliant glazing — thermally broken frames, low-E coatings, 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 and DTS rarely coexist. JV3 lets us model the building as-is and demonstrate that other elements — modern HVAC, upgraded roof, efficient lighting — compensate for the existing envelope.
Late engagement, but not too late. We fast-track the modelling and identify whether the current design passes, or what minimum changes are needed to get there before construction starts.
Innovative cladding, phase-change materials, or unconventional HVAC configurations don’t map to DTS lookup tables. JV3 modelling lets you demonstrate compliance based on actual modelled performance rather than prescribed specifications.
Multi-building developments — particularly mixed-use precincts — benefit from a unified JV3 approach. We model each building consistently, identify where headroom exists across the portfolio, and streamline the compliance pathway.
"We’re designing to exceed code and want to quantify how much better than minimum our building actually performs."
JV3 doesn’t just prove you pass — it tells you by how much. For projects targeting Green Star, NABERS, or simply a better building, JV3 modelling gives you a measurable performance benchmark against the NCC baseline.
Architectural drawings, site location, and any preliminary services information. We’ll confirm scope and turnaround within one business day.
We build a detailed 3D thermal model of your design — your geometry, your materials, your HVAC system — and create the DTS 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 JV3 report ready for your certifier or council submission. Includes the modelling methodology, assumptions, and compliance outcome. Typically 5–10 business days from finalised drawings for common topographies.
A JV3 assessment is an energy modelling method under NCC Section J that lets a commercial building demonstrate compliance by comparing its modelled annual energy use against a reference building of identical form — rather than meeting prescriptive DTS requirements element by element. If your building performs as well or better than the reference, it passes. This pathway is typically used when DTS would require expensive glazing upgrades, when the design has non-standard geometry, or when the team needs flexibility to trade off one element against another.
JV3 is worth considering when your building has large glazed areas, high window-to-wall ratios (greater than 30%), or a facade that doesn't fit DTS assumptions. It's also valuable when you have efficient HVAC or high levels of roof insulation — where those gains can offset glazing performance requirements. If a DTS check shows you're close to passing but failing on one or two elements, JV3 modelling can often find a compliant path without changing the design.
We typically start with architectural drawings at design development stage — floor plans, elevations, and sections. A preliminary services schedule helps if available, but we can work with assumptions and refine as details are confirmed. Early engagement is better: the earlier we're involved, the more options we have to influence the outcome. Send us what you have and we'll tell you honestly whether JV3 is likely to help your project.
Typically 5–10 business days from receipt of finalised drawings and services information. Where designs are still evolving, we work iteratively — providing preliminary modelling early so design decisions can be informed by compliance data rather than made in the dark.
JV3 modelling involves more work than a DTS compliance check, so yes — the assessment fee is higher. But the relevant comparison is total project cost, not consultant fee. If JV3 modelling saves $15,000–$50,000 in glazing or facade upgrades, the additional modelling cost is recovered many times over. We'll give you an honest assessment of whether the likely savings justify the additional fee before you commit.
Yes — particularly on projects where DTS requires high-performance glazing, thermally broken frames, or upgraded insulation. JV3 modelling often demonstrates compliance with simpler specifications by trading performance across the building envelope, HVAC, and lighting systems. The modelling fee is typically recovered several times over in reduced construction costs.
