Because of amendment of the Construction Standard Law, almost all houses must equip with a full time mechanical ventilation system. However, people could feel cold draft in sanitary area when the ventilation system provides sufficient volume of air. So, an investigation using thermal manikin was carried out to find out proper exhaust flow rate from thermal sensational point of view. It was found that flow rate less than 20 CMH and 50 CMH would be appropriate for bathroom and toilet, respectively to avoid uncomfortable sensation in cold season based on the evaluated EHT and PMV.
