The use of an innovative hygrothermal simulation method to develop built fabric recommendations for southern Australia

This paper will address an important gap in knowledge about the relationship between Australian regulatory energy efficiency requirements and the increased occurrence of condensation and mould in new homes. Coincidentally, Australia is the only developed nation with no comprehensive building regulations requiring hygrothermal analysis in new buildings. 40% of Australian houses constructed in the last ten years have identified condensation problems. The World Health Organisation found that residential dampness in surveyed European and North American buildings has been associated with a 50% increase in asthma rates. The methodology has included the use of hygrothermal simulation software, WUFI®. Applying local climatic conditions and expected internal temperature and relative humidity conditions, the hygrothermal simulation software can simulate and show how moisture and heat flow through the built fabric and graphically display the moisture accumulation within the built fabric. By completing the simulations in the building design phase, amendments can be made to the built fabric arrangement, and material choices, to minimise mould growth and moisture accumulation. The research has generated evidence-based recommendations for construction techniques and material arrangements that minimise moisture accumulation and subsequent mould growth in today’s regulatory compliant energy efficient homes (NCC2016 – 6 Stars) for NatHERS climates types.