Contaminant transport through the garage – House interface leakage

Many contaminants in the living space of a house, such as carbon monoxide, benzene, toluene, and ethylbenzene, originate from attached garage. As more airtight and energy-efficient houses are designed and constructed, these contaminants may be retained in indoor air for a longer period of time, jeopardizing the occupants' health. In this study, CONTAM, a multi-zone model, is employed to analyze the effect of garage-house interface on the contaminant transport from an attached garage to the living space. Parametric studies of two buildings are carried out to investigate the effect of ventilation on the transport of contaminant from the garage to living space, based on experimental data of five Effective Leakage Area (ELA) of a typical garage-house interface. The results show high concentration of indoor pollutants for typical leaky garage-house interface. Parametric simulations also indicate that the improper design of mechanical exhaust systems can cause higher infiltration of contaminants from the garage to the house, resulting in higher indoor air pollution concentration.

► A procedure is developed to evaluate the impact of garage-house interface on the dispersion of contaminant.
► Wind speed increases contaminant transport from garage but also increases exfiltration from house.
► Improper design of local exhaust system increases pressure drop and promotes contaminant transport.