The project pursues two fundamental issues: The typology of office buildings in an urban context, or rather, their mainly non-public function vis-à-vis cities, which is to be viewed as a problem; and the “refined shell construction” strategy as response to the demand for maximum flexibility associated with office buildings, which often further intensifies the previously mentioned problem.
The architecture of the new ÖKK headquarters follows an urban planning tradition embodied by the Italian urban palazzo, which although solely a private residence and deeply intertwined in the urban fabric, nevertheless manages to bring added value to the city, already by virtue of its appearance alone. With office and administration buildings, the opposite is commonly the case: they generally offer a reflection of their inner (mainly shielded from the public) function; and a row of such structures tends to contribute to a city’s desolation.
Highly important for the ÖKK building is therefore the publicly accessible and utilized ground floor, the front square, and the hall, available for both private and public events. The ÖKK building manifests this demand in in its architectural expression. The motif of the arcade has always surfaced in architectural and cultural history when the intention has been to create open passages and halls, such as market halls, churches, street arcades, and cloisters. After all, “public” means first-and-foremost spatial openness, accessibility, and open spaces.
The ÖKK building is a solid construction with five tabletop floors placed on top of one another. (At first glance, the topic of floor stacking may seem banal, but it is nonetheless one of architecture’s fundamental accomplishments in that it not only multiplies a building’s ground area, but also first introduced the transition from horizontal dispersal to urban densification into the history of human settlement.) Typically, a table’s legs are attached solidly to the tabletop, but not to the floor. Table bases have a comparably minimal bearing area. Since the floor slabs of the building are larger than a tabletop, they also require more legs to bridge the span of the slabs.
The legs’ T-form results from these conditions, or in this case, the prefabricated, exposed-concrete panels, with wide restraints on the slab edge above, in order to bear the vertical and horizontal loads below with a minimal bearing surface. When lined up in rows, bowed arcades of white exposed concrete emerge. One could also say with regard to the static construction; The arched openings that form comprise close to the maximum permitted degree of perforation in the reinforced building shell, to still permit sufficient stability and rigidity.
Once the five tabletop floors were placed on top of each other, extensive glazing could be installed behind the arched arcades, allowing not only well-lit but also wellshaded workspaces. Three-dimensional depth is created between the exterior building shell and thermal glass skin, shielding the glazing from weathering and enabling easy access for façade maintenance. At the same time, it becomes obvious that the bowed arcades are the exposed load-bearing framework rather than merely an applied conceit.
▼ south elevation 南立面
The interior consists of open-plan spaces with transparent (i.e., not visually closed) offices. The office’s glass partitions are adaptable for possible different uses in the future. At this point, the strategy of the “refined shell construction” and expressive force of the solid structure become self-evident. Natural-stone flooring and filigree concrete rib ceilings of white prefabricated exposed-concrete elements lend the spaces permanence. Commonly, office buildings are fitted with cavernous floors and ceilings, that is, using strategies for fittings and fixtures that place a premium on precisely the opposite qualities, namely, flexibility and a sense of being provisional or even non-committal.
Prefabrication of the arched panels and ribbed ceilings, deployed as “missing formwork,” significantly shortened the construction period. Moreover, the ceiling’s ribbed structure ensures good acoustic qualities, as sound-absorbent material could be inserted between the ribs.
▼meeting room 会议室
▼View of the Bündner Herrschaft 向外看
▼ peristyle 柱廊
The building services are defined by the spatial concept. Through simple peripheral window aeration, ventilation equipment on the roof draws fresh air throughout the floors and the central inner courtyard, and extracts the used air of the waste heat by means of a heat exchanger. This is then fed back into the building’s thermal circulation. Ground-water energy generated by means of a heat exchanger serves as heating or cooling source. Circulation cycles distribute it through the building’s reinforced floors. The mass of the reinforced building hereby serves not only as an oad-bearing and three-dimensional framework, but also acts to distribute and store heat, and absorb it (equivalent to spatial cooling in summer).
Client: ÖKK Landquart
Project Manager: Daniel Hoffmann / Clarissa Wacker
Civil Engineer: Fanzun AG, Chur
Site Manager: Fanzun AG, Chur
Building Technology: Amstein + Walthert AG, Zürich/Chur
Master Builder: Lazzarini AG, Chur / Andrea Pitsch AG, Thusis / Mettler AG, Chur
Facade Elemtns: Sulser AG, Trübbach
Roof Elements: Frickbau AG, Schaan
Glass Facade: Krapf AG, Metallbau, St.Gallen
Internal Glass Partitions: Strähle Raum-Systeme GmbH, Waiblingen
Natural Stone Flooring: Jann Flütsch AG, Küblis
Photographer: Ralph Feiner, Malans