Air tightness of Australian offices buildings: reality versus typical assumptions used in energy performance simulation

This study investigates the impact of air tightness assumptions on the accuracy of energy performance predictions generated by building simulation of Australian office buildings.  The first part of this paper will present the results of air leakage testing of a number of Australian office buildings performed by the author in conjunction with a commercial air leakage testing company.  The second part of the paper utilises the values from the air leakage testing in a sensitivity analysis of the impact of assumed air leakage on the predicted energy performance of office buildings in Australian climates.