Cost Analyses of Measures to Improve Residential Energy Ratings to 6 Stars - Playford North Development, South Australia
This paper reports the results of a study on the cost implications of achieving greater energy efficiency as measured by House Energy Rating(HER) ‘stars’ for new housing on a greenfield development in the northern suburbs of Adelaide. Twelve house designs typical of the housing options available from a number of builders engaged with this development were modeled using the 2nd generation Building Code of Australia (BCA) accredited energy rating assessment tool AccuRate. Where the model predicted a rating below the minimum rating (6 star) proposed under the recently agreed Commonwealth of Australia, National Energy Efficiency strategy, the designs were modified in order to improve the rating to 6 stars using a combination of specification changes and energy efficient technology options. These changes or options were then priced at prevailing building suppliers and subcontractors retail cost levels in order that an average ‘extra cost to 6 star’ and range of indicative costs to achieve 6 star housing compliance could be articulated. The results revealed that standard and currently available technologies, such a reflective foil barriers, increased insulation and low emissivity ‘e’ type glazing provide a means to achieving 6 star ratings at a modest additional cost, i.e. 1-2% of total construction and development costs.