Effects Of night-time cross-ventilation on thermal environments of residential buildings

Abstract

Night-time ventilation in the cooling period provides passive cooling effects in residential buildings with minimal energy consumption. The outdoor air supplied from natural cross-ventilation can remove overheated indoor air and provide not only comfort thermal environments but also acceptable indoor air quality for occupants of residential buildings. In this study, the one-year field long term monitoring was carried out in twelve residential buildings to survey the effects of night-time cross-ventilation on indoor environments. The windows status of the twelve samples were also simultaneously recorded during the monitoring periods. The thermal environment of the sample homes was acceptable level in most when the samples were naturally cross-ventilated. The night-time ventilation, however, was not always efficient to improve the indoor thermal environment in the sample homes, because of the enthalpy of outdoor air. It was found that the night-time ventilation is not suitable in residential buildings when the outdoor air is higher than 26℃.