As the rise in indoor temperature is due to well insulation of building construction and the increase of the amount of ventilation by mechanical ventilation equipments in recent years, many Japanese occupants complain about dryness in winter. Several strategies for preventing low humidity have been investigated in two test houses, and the temperature and indoor humidity were calculated by using BSim2002 in this study. The calculated results were in good agreement with measurement data. Furthermore, four energy-efficient strategies were assumed to use under normal residential conditions in the Standard House, and indoor humidity variations with these strategies were evaluated by BSim2002.
