Energy efficient passive ventilation system for Japanese conventional wooden single family house.

Purpose of this study is establishment of energy efficient natural ventilation system for Japanese conventional wooden single-family house, by using humidity-controlled extract units (code name: GHN).To evaluate the effect on energy performance and indoor air quality by adapting the GHN to the passive stack ventilation system, airflow rate, humidity, temperature and CO2 concentration are measured over a period of one year in an experimental house. Numerical simulation on temperature, humidity and airflow is also carried out.Measurement results show that the GHN functions thoroughly according to indoor relative humidity and stabilizes CO2 concentration in lower level. The result of numerical simulation indicates that this system makes it possible to avoid harsh indoor dryness and save heating energy in winter.