User-controlled exhaust fan ventilation in one-family houses.

A group of 18 identical well-insulated experimental houses in Sweden, utilizing a user controlled exhaust fan ventilation system, was monitored during 1985- 1986. The ventilation rate can be controlled by the user by adjusting the fan speed with a conveniently located three-way switch. No heat recovery is provided for, the idea being that the average ventilation rate will be low, thereby saving energy. The houses are described. The results from measurements of ventilation efficiency, ventilation rates. run time of fan speeds and energy consumption are presented. The investigation has shown that a simplified exhaust fan ventilation system can lead to a comfortable indoor climate. The results so far indicate that the average yearly consumption of electricity for space heating, hot water heating and household use will be as predicted i.e. 12,000 kwh, compared with approximately 20,000 kwh for a well-built house that meets the current Swedish National Building Code. This energy saving was achieved by insulating and tightening the houses very well and installing a user controlled ventilation system.