When the rigid (yet low cost) Deemed to Satisfy method looks like implementation will be costly during the construction phase, our clients seek compliance using JV3 Modelling (i.e. Verification Method). If professionally performed, JV3 modelling can allow changing double glazed windows to single glazed windows by increasing the insulation elsewhere in the building.

When performing JV3 modelling, we have always been able to reduce construction costs by more than the value of our fee, which is why we offer

A unique Service Guarantee:

If we can’t reduce your construction costs by more than the value of our JV3 service fee, then we will only charge you the 25% deposit.


JV3 modelling is an alternative compliance assessment report to a Deemed to Satisfy report.  JV3 modelling (a verification method and performance solution) is a compliance approach that requires modelling the proposed building with computer tools.  This alternative method compares the thermal performance of the proposed building with the same building that is compliant with the minimum Deemed to Satisfy insulations and thermal requirements (i.e. NCC reference building).  The outcome is simple – pass or fail.  In order to pass the energy efficiency requirement test, annual greenhouse gas emissions from the proposed building must be less than that of the NCC reference building.

The Alternative Method JV3 compliance path is simple, and works all the time when the Deemed to Satisfy approach provides an undesirable solution, or doesn’t meet the client’s requirements.


  • Provides energy compliance to the NCC in a more flexible manner.
  • A proven method of reducing construction costs.
  • Allows replacing high-cost energy saving measures with low-cost options (e.g. single-glazed windows instead of double glazed).
  • Has no limitation in applying customized building materials and glazing options.
  • Allows offsetting the building energy demand with the use of onsite renewable solar systems (electricity or solar hot water).
  • Allows offsetting the use of low-cost HVAC solutions with other low-cost energy efficiency measures.
  • Your HVAC engineer can use the estimated hour-by-hour energy demand from different building zones to perform a preliminary design and hourly feasibility assessment of different energy system options.
  • Reduce/increase insulation in some areas of the building, and offset it by a change in insulation somewhere else in the building fabric.
  • Increase/reduce the amount of light you receive inside the building by adjusting the SHGC factor of your glazing to your desired value.

While the Deemed to Satisfy method is low cost and quite fast to obtain, it doesn’t consider the thermal interaction between all building fabric components.  It therefore doesn’t necessarily produce the most cost effective built solution all the time. Solutions under DTS can be prohibitively expensive to install.

The JV3 method, on the other hand, utilises holistic modelling of the entire building, and at Energy Compliance, with no exception to date, has always satisfied our clients’ construction cost reduction requirements.


The National Construction Code Building Energy Modelling requires that:

  • The building be firstly modelled in accordance with the Deemed to Satisfy (DTS) provisions (called the reference building).
  • The building, with all its details as per client’s requirements or as per Energy Compliance’s recommendations is remodelled using the JV3 approach (called the proposed building).
  • Finally, heating and cooling loads and greenhouse gas emissions of the reference building are compared to that of the proposed building, and if the proposed building generates less greenhouse gas emissions than the reference building, then the proposed building passes the NCC energy efficiency test.

This JV3 approach provides the flexibility, for example, to specify increased insulation in the roof space to minimize the glazing requirements (e.g. double or triple glazing), thereby providing an overall construction cost saving to meet energy compliance requirements.




Here is a simple example that shows the logic behind the cost efficiency of the JV3 alternative energy modelling solution.

For instance, let’s assume that a client has selected Deemed to Satisfy (DtS) approach for meeting NCC Section J, energy efficiency compliance. The glazing calculator in NCC requires installing tripled glazed windows to meet minimum NCC compliance requirements which are apparently, going to be very expensive to install. The reason is that DTS is an elemental approach and doesn’t consider the overall annual performance and the interaction between glazing and other elements of the building and.

JV3 on the other had only considered the overall building performance and annual heating cooling demand (and subsequent greenhouse emissions) as its compliance criteria. 

At energy compliance, we will first investigate the DtS solution limits and if the clients decide to assess some construction cost reductions, we will offer solutions like an all single glazed window with shading device to some of the east-west windows. Shading device can be an external roller shutter or similar. Now, how can a shutter reduce glazing cost?

The broad capabilities in JV3 modelling tools allow, for instance, to model a shutter that can be opened and closed in different seasons. This allows modelling shutter in an open position to maximize natural heat gain from sun during the winter (when you need it) and blocks solar heat gain during summertime when your building doesn’t need it. Getting more heat from the sun during winter and blocking heat source in summer allows reducing the overall annual heating and cooling energy demand of the proposed building compared with the same building with NCC minimum triple glazed windows (reference building).

Summary of benefits

A JV3 Solution like adding shutter will:

  • Assist the client to save in construction costs
  • Provide improved living comfort for the future occupants
  • Minimize greenhouse emissions from the building
  • Avoid making decisions based rules of thumb or a salesmen promises




The JV3 method is strictly regulated under the NCC, but the essence is in the flexibility of modelling and the power of modelling tools that allow almost any modelling changes.  JV3 modelling allows three dimensional and hour-by-hour modelling of a commercial building to minimize construction costs. 

Building classes that can benefit from the JV3 method

JV3 alternative modelling can be used for all commercial buildings (Classes 3, 5,6,7,8 and 9).  Apartments (class 2 buildings) and the residential components of commercial buildings (classes 4) can be modelled using the Verification Using Reference Building, VURB method.

JV3 Modelling Tools

JV3 modelling, in essence, is similar to NatHERS modelling, yet with far more capabilities.  The software used should be capable of hourly energy modelling of a building and should comply with the ABCB’s set of regulations.

At Energy Compliance, we utilise the state-of-the-art TRNSYS design platform that allows hourly thermal modelling of the building (in 3D).  This is a comprehensive research-level modelling tool that complies with ABCB modelling software requirements.  At Energy Compliance, we have a reputation for getting the best result at a competitive price for even the most difficult building designs.

Energy Compliance’s use of TRNSYS for JV3 modelling further allows us to perform hourly modelling of multiple renewable energy systems in a single model. This allows the client to consider the dynamic interaction between different energy systems including Geothermal, Solar Thermal & Storage, Solar Electricity & Storage, all in a single model for a typical year, and to offset the reduced greenhouse emissions as a result of using renewable energy by using less insulation to the building and saving construction costs.



Glazing can be a significant construction cost component, and how the National Construction Code (NCC) handles glazing often makes it much more expensive than necessary.

This unnecessary cost impost is due to the default energy assessment method for glazing in buildings under the Deemed to Satisfy (DtS) provisions, wherein glazing is assessed in isolation to the rest of the building fabric (i.e. floors and roof).  Fortunately, the NCC allows an alternative solution for energy efficiency compliance assessment, called JV3.  

The JV3 assessment method provides the ability to model glazing and all other building components as a system.  So, for example, specifying a lower thermal performance window can be offset by increasing the amount of insulation in the roof space.

Why choose Energy Compliance team as your energy assessment consultants?



Fast turnaround

Bigger saving

Preliminary design of HVAC system

Feasibility assessment

Very competitive rates for all sized projects

Guaranteed delivery in 5 to 10 days

Guaranteed lower construction costs

Energy Compliance is a division of Geoflow Australia, which provides detailed feasibility assessments and preliminary designs for renewable energy system and conventional HVAC options.



If we can’t reduce your construction costs by more than the value of our JV3 service fee, then we will only charge you the 25% deposit.

You won’t get this guarantee anywhere else!



At Energy Compliance, we provide expert JV3 modelling services to architects, developers and even other national energy assessment businesses.  Our clients are very appreciative, and enjoy large construction cost savings, with single-pane glazing replacing double/triple-pane glazing. 

Our unique Service Guarantee provides real peace of mind for clients, who are comfortable investing a small fee in return for major construction cost savings.

If you have a project with high glazing costs, we are here to help you.

We also provide other unique energy efficiency solutions for large scale commercial applications, such as shopping centres and industrial process heating/cooling.

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