Sweden paved the way for the success of the "low-energy house". Experience with complicated and unreliable technology had taught them the right way to do things: a high level of airtightness, very
good insulation, good windows, reliable mechanical ventilation. Hans Eek is a leading pioneer in Sweden - the experiences with construction research are directly reflected in his life story: from
the "technological christmas tree" and the super-low-energy house to the Passive House. In the picture, terraced houses of the German-Swedish Ingolstadt-Halmstad Projekt can be seen.
These aren't Passive Houses, but it's only a small step further to the Passive House.
Hans Eek was and is a cooperating partner for all stages of the Passive House development.