The sick house syndrome has become a serious problem in Japan recently. It is important tospecify and quantify the source of chemical pollution. In this study, passive samplers for concentration of chemical substances in the air, ADSEC for emission rate of chemical substances from building materials and PFT method for ventilation rate in a room were developed. These passive methods enable investigation of many houses at a time. Indoor air quality of a newly built house was measured by these passive methods in summer and winter. The emission rates from building materials were low, but the ventilation rate in the room was low especially in winter.