Demand controlled ventilation systems in three Finnish demonstration dwelling houses.

In this study the multifamily demonstration buildings with demand controlled ventilation systems are discussed. Furthermore,the heating systems together with demand controlledventilation are looked at.There are given examples of the centralized supply and exhaustventilation system, the centralized exhaust ventilation systemand the apartment based ventilation system. All the Systemsare mechanical, natural ventilation is not discussed here. Incold climates natural ventilation, i.e. opening of the windows,can't meet the requirements on good indoor air quality andthermal comfort and leads to poor energy economy