The cost effectiveness of housing thermal performance improvements in saving C02-e

To reduce the CO₂ emissions associated with the energy needed to heat and/or cool houses, the Building Code of Australia 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 to 10 stars. Currently, all states and territories in Australia require a minimum 5- or 6-star performance; however, this is likely to be increased incrementally in the next decade. Increasing a house's thermal performance generally increases its embodied emissions. However, this is rarely considered when assessing the cost effectiveness (in saving CO₂ emissions) of thermal performance measures. This article examines the cost effectiveness of incremental thermal performance improvements, taking into account their embodied emissions. The results show that the cost effectiveness of achieving a certain level of thermal performance varies significantly depending on the methods and materials used.