Akademiska Hus AB has the ambition to halve the energy cost from the year 2000 to 2025. Between 2006 and 2010 the Natural Science Building was renovated completely, and a new presence- and pressure controlled air treatment system was installed. The results show that the investments reduced the heat energy consumption with about 80 percent and the building electricity consumption with about 85 percent. Akademiska Hus AB Region North, had in 2010 built the most energy efficient office building in the region, and still the building is one of the most energy efficient buildings in Umeå. The conclusion of the project is that it is possible with quite easy and also viable investments build more energy efficient than the building Code and the building industry in common requires. A strategic work, ambitious objectives and a conscious and courageous leadership seems to be just as important.