The Changes Associated with Efficient Dwellings Project report was commissioned by the Department of the Environment and Energy and produced by the Moreland Energy Foundation. The project conducted an independent study into how the introduction of the 6 star energy efficiency standard has been responded to by industry.

A qualitative research component including 17 interviews and a survey with 187 respondents was conducted with industry representatives and stakeholders participating. A quantitative component was also conducted with 58 dwellings examined with regards to the costs of achieving a 6 star or beyond performance ranting.

Key findings in the report include:

• The majority of stakeholders agreed that an increase in the level of specification in glazing and insulation were the main changes in response to BCA 2010.
• Views with regards to the level of cost incurred by the BCA 2010 varied from less than $2000 to more than $5000.
• Incremental cost analysis showed fairly consistent cost increases for Class 1 dwellings at $2700 for a 150sqm dwelling.
• Stakeholders were in general agreement that costs could be managed more effectively with the implementation of alternative strategies however competing priorities such as daylight amenity and orientation restrictions were also recognised.
• Industry capacity was acknowledged as a significant factor in the management of increased costs associated with the stringency increase.
• A learning rate is evident in the research with an annual learning rate of 7.5% per year observed.
• The application of the increased costs combined with the observed learning rate suggest that 7 star dwellings could be cost effective when using an indicative cost benefit analysis.

The report notes the difficulty in sourcing drawing and specifications data from industry as an issue with regards to confidence in the results presented. The report authors recommend further research be done in the area of setting trajectories and improving compliance.

The report will help to inform the further development of building energy efficiency via Measure 31.2 of the National Energy Productivity Plan (NEPP).

More information here.