For countries with a cold climate the large difference (30-60°C) in winter between indoor and outdoor temperatures leads to a) large heat losses in ventilation systems; b) moisture freezing at the systems exit and c) great reduction in the indoor humidity. Here we present a new approach for regenerating heat and moisture in ventilation systems in cold climates which allows resolution of these problems. The method has been tested under climatic conditions of South Siberia (winter 2005-2006). Technical, economic and social aspects of this method are discussed.