Applicability and evaluation of airtightness prediction method using pressure differences under actual climate conditions

The blower door test and tracer gas test methods are commonly used to measure airtightness and infiltration in buildings. Nonetheless, these methods can be costly and time-consuming. To address these issues, the air pressure measurement and prediction system (APMPS) was proposed. This method predicts the airtightness of a building by measuring the differential pressure across its components. However, the effectiveness of this method has yet to be verified under various conditions. The aim of this study is to analyze the effectiveness of the APMPS under different building and weather conditions. Three residential buildings of varying heights were analyzed, and measurement of differential pressure and temperature differences were taken. The actual airtightness was determined using blower door tests, and the results were compared to the predicted airtightness calculated by the APMPS. The results indicate that APMPS is effective in predicting building airtightness, with the majority of predicted values falling within the range of 2-3 h−1 at 50 Pa. The accuracy of the predictions improved as the building height, differences in indoor and outdoor temperatures, and differential pressure increased. Furthermore, a significant correlation was observed between the error rate, height difference, and differential pressure at a significance level of 1%. The APMPS has demonstrated its value as reliable tool for accurately predicting the airtightness of multi-story buildings under various conditions. This method simplifies the measurement of airtightness in building components, which is crucial for evaluating building energy demand and air quality.