Since the BCA section J; JV3 energy modelling protocol was introduced in 2006, energy modelling has been used successfully in achieving the compliance of buildings to meet the BCA performance requirements.
The use of the JV3 protocol has steadily increased over the last nine years, with industry members just starting to understand the power and versatility of the process.
While the use of energy modelling is increasing, there is still a strong reliance on using the Deemed-to-Satisfy (DtS) provisions. I have personally noticed an increase in use of the JV3 protocol or JV3 based performance solutions for approximately 20 per cent of projects that I have completed in the last 12 months. While this is a positive step, there are still too many projects (80 per cent in my experience) relying on the simplified, and more expensive, DtS provisions. Simple projects such as single storey, slab on ground, office buildings do not suffer from using the DtS provisions, however most buildings other than the type noted before, should use the benefits of the JV3 protocol.
The JV3 protocol, when used correctly, provides a more cost effective solution for the built environment. The major area where costs can be reduced and building performance can be increased is in the specification of glazing and insulation. Some applications of insulation are quite costly, particularly under slab insulation in warm climate zones. Australian Building Codes Board (ABCB) climate zones 1, 2, and 3 are warm climates where shaded under crofts and external shading have a larger impact on the energy performance of the building than under croft insulation. By using the JV3 protocol to assess all the impacts on the building and comparing it to the insulation performance of the DtS provisions, the under croft insulation can be typically be deleted. This is one simple example of the benefit of the JV3 protocol.
Other benefits are in the application of internal wall insulation, in particular around fire rated areas of buildings. Fire rated materials are generally not good thermal insulating materials, hence a double wall needs to be built – one to meet fire rating requirements and a second wall attached to the first to meet BCA section J compliance requirements. This can be a very costly exercise and can result in an increase to the overall footprint of the building as these double walls are thicker than may be required. The JV3 protocol and other alternative solutions can provide a compliance assessment for these walls that does not have the penalties associated with the DtS provisions.
The JV3 protocol allows the direct assessment of the benefits of the positive and negative aspects of a design and provides the opportunity to save money in design, construction and during the operation of a building. The JV3 protocol does not restrict the use of building materials and increase the thickness of walls as the DtS provisions do. It is possible to provide a balanced building performance that allows for the reduction of insulation in some areas of the building while increasing the performance in areas of the building where the materials will have a greater impact.
The JV3 protocol has provided engineering and building physics professionals the ability to provide industry a clear pathway for determination of performance solutions and direct verification methods that allow compliance assessment to be more robust and more flexible in achieving the performance requirements of the BCA.