Five ground floor passageways provide access from the outside to the central courtyard and form the entrances to the vertical circulation zones that divide the overall structure into five segments. Housed on the ground floor are communal facilities like workshops, computer rooms and spaces for washing machines, as well as bicycle stores on the same level as the external pavings. On each of the upper floors, 12 rooms in every segment are laid out in various arrangements to form a dwelling group with communal spaces. The rooms of the 380 residents are located on the outside of the building with views of the surroundings. The corridors, the common rooms and the large balcony areas are oriented to the communal internal courtyard, which forms the focal point of the scheme. The plywood cladding along the curved corridor walls is printed with a graphic design created by the artists Aggebo & Henriksen. All rooms are fitted with sound-insulating doors, large inbuilt plywood furnishings and sanitary cells.
The Lundgaard & Tranberg practice seeks to apply independent architectural concepts in the design and implementation of its projects. There is a pronouncedly regional aspect to its work, expressing a contextual approach to architecture. We address every task with an investigatory curiosity, looking for specific features of the location and the programme to lend every scheme an unmistakable identity and root it strongly in its surroundings. We are interested not only in the architectural form, but in the links between form, function, structure and materials.
Design quality is the best guarantee of permanence in architecture: ensuring that buildings, cities and landscapes remain attractive for many generations. Genuine architectural quality is expressed through buildings that function well, that are filled with life and activity, that are appreciated by users and observers alike, that are modern, yet that also age with dignity. They should be full of contrasts; they should be sensuous, descriptive and contain surprises. Our office is involved with all stages of architecture: the way in which individual structures fit into a given context, the urban and landscape spaces resulting from this, the building itself as a formal and spatial composition and the way it responds to the brief, the details and material qualities of the various elements, people’s sensual perceptions of a development, as well as life within and between the buildings.
This approach is evident in the Tietgen hall of residence for students. Rarely can architectural goals of this kind be implemented in such a pure form as was possible on this occasion, however. The idea of a circular building seemed intuitively appropriate in terms of both the urban context and the inner organization of a student hostel, where the community plays a central role. The cylindrical form was at odds with the rectilinear development plan, however. We therefore rejected the idea for the time being and investigated other solutions. None of these had the strength or clarity of the circular form, though, which meant that we kept returning in discussions to the original concept. Aspects of this kind commonly occur in any competition and may lead to disqualification. We decided to take the risk, and after that the development of the scheme was fairly simple.
The basic form determines the internal organization. The individual student rooms were placed on the outside of the circle and the communal spaces on the inside, overlooking the courtyard. The layout is therefore based on a radial structure. Architecturally, the cylinder is both formalistic and monumental in character, and it is not immediately an expression of housing for young people. We felt, therefore, that it was important to develop variations on the basic circular theme and to incorporate a certain elasticity and dynamic – to emphasize the individual as opposed to the community, and to give every location its own significance within the overall context.
The competition had called for a clear form and a functional organization of the spatial structure in combination with an unusual structural principle and expressive variations in the design. Fortunately, the jury showed understanding for our vision.
The further development of the project was supported by a client who wanted to create an unusual building and who also had the rare gift of understanding the design process. Among the main goals of the further planning were simplification and the provision of maximum scope for repetition in order to achieve design complexity and to reduce construction costs. The expressive variations on the design were morphologically systematized in the planning – a compositional order that has its own inner logic geometrically and structurally. The number of room types was reduced to three, which still allowed the creation of more than 30 different dwelling combinations.
Special importance was attached to the planning of the load-bearing structure, which consists of a combination of insitu concrete, precast concrete elements and prestressed steel cables. Since the structure is visible throughout the building, the details, materials and coloration were carefully harmonized. The robust concept can be seen in the formal clarity and the tectonic balance that remains evident even in the finished building.
The Tietgen Hall of Residence adjoins a largely green landscaped area that extends to the canal. Grass strips 180 cm wide are interwoven with 180 × 60 cm insitu concrete slabs with a brushed surface. These are laid in the general direction of movement. To the west of the building, a broad area of wood decking used for leisure purposes marks the transition to the canal, which flows through the city.
The courtyard is a simple, robustly designed open space that forms a contrast to the building itself yet at the same time enters into a dialogue with it. This space has a number of functions. It is a large foyer from where one gains an initial impression of the development as a whole. It also forms a natural link and line of access to the internal doors and corridors. Last, but not least, it is the most important meeting place for the community as a whole, providing ample space for outdoor activities, such as meals, concerts and parties.
The courtyard consists of just a few elements. The sunken lawn area is planted with closely spaced white willows, which are pruned every three years. The tips are left uncut so that the trees can grow higher and retain their distinctive features. The grassed area is enclosed within a 180-cm-wide fibrated-concrete curved bench with a wooden top. Between the building and the bench are insitu concrete paving slabs inlaid with adobe wood strips, which lend the area a lively, varied character.
The circular form of the student home is articulated into five sections by vertical incisions that afford access to the courtyard and also separate the segments structurally (with the exception of vertical loads from the open intermediate platforms in steel and the access stairs to the upper floors). The circular structure incorporates 45 two-storey cantilevered concrete boxes in three different sizes, containing kitchens, common rooms and utility spaces. With a free span of 8 m, the kitchen elements are the largest of these; fully loaded, they weigh roughly 250 tonnes. This necessitated extensive planning and preliminary tests.
A cantilevered construction method was used that is known from bridge building. The principle is simple and obviates the need for elaborate, expensive and time-consuming scaffolding. A careful investigation of various construction methods was carried out at the beginning of the design phase.
Initially, it seemed only logical to build the cantilevered boxes as lightweight steel structures. In the end, though, a primary system consisting of two-storey precast concrete wall elements proved to be the best solution.These are horizontally prestressed with high-strength steel cables, which ensures a permanent compression zone in the vertical section between the main seven-storey-high structural elements and the cantilevered boxes. The two-storey wall elements are much less susceptible to vibration and also provide a more efficient climatic shield than lightweight structures. The floor construction between these wall units consists of a relatively thin concrete slab on prefabricated steel beams (ill. 4).
The two-storey-high concrete wall elements are raised on to storey-height precast brackets or ledges fixed to the main structure and tied to this with high-tensile steel cables (ill. 7). Concrete slabs were then cast between the two wall elements. In constructing the kitchen boxes, this procedure was repeated until three two-storey elements had been added in each wall. The common rooms consist of two elements in each wall, and the utility rooms of only one two-storey element in each wall. The boxes were finally clad in gold-coloured pinchbeck sheeting.
To prevent the weight of the cantilevered boxes causing the seven-storey main building to tip over towards the inner circle, the primary structure was vertically prestressed by 65 high-strength steel cables at the back of the building (ill. 2). These cables are anchored in the circular external basement wall, which, in view of the great loading from the building above and the high groundwater level here, was constructed in solid in-situ concrete. Fixed at the top of this wall are anchor bars that secure the structure in tension-tested limestone 15–20 metres below ground level.
The ground floor is very open. The six storeys above are supported by solid three-legged in-situ concrete frames with untreated surfaces. The structural system of the upper six storeys consists of precast concrete elements.
The construction method is rational, effective and highly impressive. The prestressing pro-cess allows the creation of exceptional structures, using precast concrete elements.
In 2002, the Nordea Danmark Foundation wished to erect a new student hall of residence in Copenhagen in a state-of-the-art form of construction. This was to be “a student hall of the future” and be named after C. F. Tietgen, one of the country’s most successful businessmen. It was also to be inspired by traditional buildings of this type and to provide an attractive environment for living and studying. The competition participants were encouraged to give free rein to their imagination, with no budget limits initially – a unique situation. A central aim was to create a location that would inspire a sense of community and stimulate interdisciplinary, intercultural encounters and a tolerant atmosphere.
Situated in the recently developed Ørestaden district of the city, the curved lines of the new development – inspired by Chinese models – were to be juxtaposed with the existing rectilinear layout of the area. Opened in May 2007, the Tietgen student home has already become a symbol of creativity, quality, tolerance, originality, global vision and the ability to reinterpret traditions in a new way. A number of rooms are reserved specially for foreign students. The foundation is pleased not only with the architectural concept, but with the way the underlying ideas have been brought to life. Erecting a building alone is not enough in itself, though. Motivated students and a pro-fessional organization are necessary to fill it with intellectual life and a sense of community.
Johanna Binder: I’m here for half a year as an exchange student. I didn’t even have to bring furniture with me. Community life is important here. I spend most of my free time in the kitchen or on the balcony, and at weekends, there’s often something going on in the courtyard. When this is in the shade in the afternoon, everything shifts to the large balconies.
Mads Dreisig Johansen: The architecture plays a big role in creating the atmosphere here. In the courtyard and on the terrace, you feel part of a large community. People often envy me for the fact that I live here. I know I’m lucky. Applications are reviewed by a committee of four residents and an administrative assistant, and there are waiting lists, of course.
Ayoe Ingemann Buhl: Depending how much contact you want, you can find it in the communal kitchen and on all floors of the building; or you can withdraw. The soundproofing is very good. I don’t just live in my room, but all over the building. I spend a lot of time in the kitchen and use the communal areas, like the workshops and the fitness rooms. I have one of the smaller rooms in the building and pay DKK 3,000 (™400) a month. It’s well worth it.
Pernille Schmidt: I’m involved a lot in social activities here and know plenty of people. The group spaces with their different themes are meeting points for everyone. There are three levels of privacy within the groups: the kitchen is our real living room; there’s another space where we all meet; and then your own private room. The rooms are relatively big: often you don’t notice that you haven’t been out of the building for days. There’s an aesthetically inspiring atmosphere about the place. Maybe we’ll have problems later in a normal flat.
