Thermal comfort evaluation of natural ventilation mode: case study of a high-rise residential building

Natural ventilation can be used as a low-cost alternative to mechanical ventilation. Bearing in mind that ventilation mode plays an important role in natural ventilation performance, the current study investigates the effectiveness of two major natural ventilation modes (i.e. single-sided and cross ventilation) in providing thermal comfort for occupants of high-rise residential buildings in cooling dominant climates. Measurements of air velocity, temperature and relative humidity were carried out in a unit located in a high-rise residential building in Brisbane, Australia. Both single-sided and cross ventilation settings were examined in two consecutive days in summer. The extended Predicted Mean Vote (PMV) and Predicted Percentage of Dissatisfaction (PPD) were calculated and results showed a considerably better performance of cross ventilation over single-sided ventilation. Cross ventilation could provide thermal comfort in a typical hot summer day for most of the day (greater than 70% of the time), while, for single-sided ventilation the thermal conditions of internal spaces was comfortable for only 1% of the time.