Gymnasium and sports hall, Koprivnica, Croatia

‘Koprivnica – Spirit of Mega’; a town with the lowest number of college graduates in Croatia announced the rebellious competition program for 900 scholars and 2000 spectators in 2003. The site of the high school building and a sports hall, in front of the American-like housing suburb periphery, is located at the end of a series of ambitious town interventions – mega elements.

‘Tabula rasa’; The contact site of these ‘two worlds’ is radically divided into two parts, black and green, full and empty, spiritual and physical, one facing the city and the other facing the residential suburbia.
The new building complex arises between these two extremes. An enigmatic compressed mono-volume of the gymnasium and sports hall complex with intricate spatial relations in contrast to a vast plain landscape, placed centrally on the plot, forms a gymnasium -a common place- a contrasting provocative whole lacking a foreground or background, without hierarchy or authority.
The «common place» concept examines the stability of the hybrid, and enables the most diverse interpretations both in terms of use and interpretation of significance of the building.
The selection of an abstract mono-volume, with a transparent membrane is a radical break with the modernist tradition of building schools and sports facilities as three-dimensional interpretations of bureaucratic disposition schemes. In addition to the public-private partnership in construction of the gymnasium and sports hall in Koprivnica, the idea of building two complementary urban facilities in a single building also arose. Hybrid facilities overlap with the public-private partnership concept, where the hybrid complex is leased and managed independently of the newly formed institution. The spatial and visual overlapping of the facilities and the synergy of use constitute the basic operative logic underlying the building.
The structure of the building is reinforced concrete on the ground floor, while the upper floors are realized with dry assembled ‘H’ shaped steel elements. The classrooms floors have thin Slim-deck flooring, made up of trapezoid section lightweight galvanized sheet steel and cast concrete.
The roof of the sports hall is made using a specially designed grid work of right-angled elements and joints in steel. Generally, all the materials are available on the standard building market (lightning, anodised aluminium window frames, metal parapet grilles, Profilit industrial opal glass) and there is no finishing when unnecessary, as in case of the floor soffits which are left unfinished.
Because of its high cost there is no air conditioning in the gym, so system of shutters above the sports hall and the ducts through the cantilevered classrooms of the top floor ensure a constant flow of cool air during the summer months, while the double polycarbonate skin creates a ‘green house effect’ in winter. The translucent skin, illuminated at night, radiates the even and turns the building into public condenser, an iconic and symbolic place for the youngsters of Koprivnica.