The 1950s building was made of concrete and had a concrete form of expression. During the annex/reconstruction in the 1980s, both the newer and older sections were clad with metal sheeting, in order to provide the best protection from the elements, which can be very extreme in this area. The most significant changes from the 1950s-1980s were however in the overall architectural modifications - a transition from a light building that hovers above Klubben to a heavier building that seems to be emerging from the hill.