Nathan Taylor

In this study, a cost and benefit analysis of the expected thermal performance effects of various insulation upgrades for a typical Housing NZ low income state house was conducted. The particular house chosen is one of 3600 on the South Island of New Zealand that are undergoing insulation retrofits in a national programme to reduce energy use and CO2 emissions while improving the health conditions in state-owned housing. The house was simulated using both steady state and dynamic modelling tools, and the results were validated against the monitored performance of the actual house. The various locally available upgrades were simulated over a variety of heating schedules to provide a broad view of how the retrofit will change the range of comfort vs. energy consumption possibilities available to the tenant. In addition, a preliminary economic cost-benefit analysis was performed for different comfort levels and space heating schedules before and after the upgrades. This is offered as an initial guide to help Dunedin homeowners evaluate the potential benefits of retrofitting energy efficiency improvements.