Estimation of air infiltration for Australian housing energy analysis

Abstract

This study presents an integrated air flow model for AccuRate, a benchmark housing energy star-rating tool widely used in Australia. The model was developed by implementing a network multi-zonal infiltration model into an existing large opening model. Case studies using 10 houses in Melbourne, Australia, showed that on average the predicted infiltration rates are within 12.6% of the blower-door test results with a standard deviation of 1.6%. The model study also showed that on average the infiltration rates of the 10 houses could be reduced around 52% by sealing major air leakage pathways, which can result in an average of 7% reduction in the annual space heating and cooling loads for the 10 houses. It was also found that an annual hourly energy performance simulation using the new air flow model requires around 15 min in comparison with around 1 min using the existing simple infiltration model in the AccuRate engine.