The costs of improving the thermal performance of houses in a cool-temperate climate
Authors: McLeod, Philip ; Fay, Roger
To minimise the energy needed to heat and/or cool houses, the Building Code of Australia (BCA) requires that new houses meet a minimum level of thermal performance. A star rating system is used to indicate the level of thermal performance a house achieves. Ratings range from 0-10 stars. Theoretically, the more stars, the less energy is required for space heating and/or cooling. Currently, most states and territories in Australia require a minimum 5 star performance. However, a 7-8 star rating will be necessary for the thermal performance of Australian housing to be comparable to that of housing in many other developed nations.
This paper examines the capital cost and design implications of significantly improving the thermal performance of brick veneer houses in a cool temperate climate. The results show that the cost of achieving a certain level of thermal performance varies significantly depending on the methods and materials used, although improvements in thermal performance can be made for little or no cost.