The jury’s assessment of the winning design

Kees Christiaanse
The jury’s assessment of the winning design by Xaveer de Geyter Architects, Topotek 1 Architektur, and Topotek 1 Landschaftsarchitekten (Brussels, Zurich & Berlin)

Fotos: Marie Schwarze

\\ The design uses a much more substantial open space connecting the two parts of the site in order to counter the division of the buildings necessitated by the visual “cut-through”, and this idea is immediately compelling. The link between Ludwigstrasse and the harbor basin, which is desirable from an urban planning perspective, remains in place but does not appear divisive; rather, it seems a natural and necessary point of access to the new HfG campus, which is organized around this courtyard like a small town. \\

The large volume of the four- to five-story building follows the bend in the line of buildings and the boundaries, as required by the development plan, and makes extensive use of the plot right up to its edges. This provides the necessary conditions for creating a large, rectangular 190 m x 26 m courtyard that is clearly assigned to the university and appears to be cut out of the building. Since the garden courtyard does not follow the bend in the building, it acts as a strong connecting force across the visual cut-through. In the western section, this interlocking creates the necessary spatial depths for the foyer, event, and exhibition areas. \\ Around the courtyard, the different uses are positioned within an equally clear, constructive edifice that appears robust and flexible for future adaptations, too. With the ingenious angling of the façades in the area of the incision for the cut-through, the design avoids the acute angles created by urban planning. This results in a funnel-shaped, inviting gesture on both the city side and the riverside, and the cut-through loses its axial dominance. The axis of the new campus courtyard, meanwhile, is strengthened and has an inviting effect. Discreet regulation of access to the well-structured campus garden through landscape planning measures is still to be developed. \\ The open space responds to the urban figure of the large “block” by providing an internal, park-like courtyard. Both the entrance setting from Ludwigstrasse and the opening toward the riverbank are well resolved. It will be necessary to check whether the desirable seating steps on the riverside are feasible, and the entrance area and the square on the Main could both do with more trees. The leafy strip as a connecting pathway across the stone square is a clever solution. Despite its size, the large campus park in the courtyard is divided into various sub-spaces with different functions, although the interior-exterior relationships will need to be designed in a much more differentiated way later on. The illustrations of the courtyard show how important it is to have large trees with dimensions of this kind (26 m wide), and the large pines depicted seem fundamentally suitable here. Planting is particularly relevant if the student accommodation is to remain in the location proposed here. Going forward, options would also need to be developed for demarcating the outdoor spaces intended for public and restricted access. \\ The main and side entrances are located at the front of the building in the area of the cut-through. A clearer sense of an entrance needs to be elaborated here in the planning. The south-western entrance on Hafenallee leads to the elevated foyer, from which the large staircase, designed as a communication zone with seating, leads to the library on the first floor. The gallery is prominently positioned on Hafenallee and promises an optimal connection to the public urban space. The dining area of the cafeteria is located at the northern end of the western part of the building with an attractive outdoor terrace in the campus courtyard. \\ However, the layout of the cafeteria floor plan as presented is not functional and requires further definition in line with the specifications of the competition text. The functional areas need to be optimized, possibly through space swaps with other uses. The food counter should be a separate structure in order to make the dining area multifunctional and usable as a workplace for students outside of opening hours. \\ The workshop, studio, and teaching area on construction site B impresses with its industrially robust spaciousness. The single-sided circulation with so-called buffer zones on the south side promises a lively, well-lit working environment with optimal meeting and appropriation spaces.

All the designs submitted for the architectural competition for the new HfG building in the harbor area of Offenbach go on public display from January 27 to 31, 2023.

Photo: Lea Kulens

The connection of the two lower studio floors via a gallery in this area further supports this approach. \\ The long and gridded design of the building structure on construction site B is intended as an homage to the industrial buildings along the River Main, while the subtraction of individual volumes breaks up the blocks of the structure and adds rhythm. The resulting special-purpose spaces are each two to three stories high and are positioned differently in the ground plan as inner courtyards or sections flanking the façade. This creates promising spaces for exhibitions and communication. \\ The jury feels that the multiple coding of the surrounding “bioclimatic gallery” as an access, work, and exhibition area as well as a climatic buffer zone is a very attractive element for the future university. The cascade of uses – studio-gallery-garden – can enable highly flexible working and exhibiting, while in the southern block students will likewise have the opportunity to use the access zone as a window onto Hafenallee. The proportion of access areas is too great, however, and should be optimized as far as possible in the event of further specification. \\ Access to the buildings works well. The possibility of a turning space to accommodate even large trucks in the area of the studio wing is a notably positive feature. \\ The spatial location and organization of the student residence was the subject of controversy. A less central location at the north-eastern end of the building or a separate structure in the area of the eastern boundary of the site should be investigated in the course of further specification. Here, it’s important to make sure that residents retain their privacy in relation to the university operations (social control).

\\ The zones for technical facilities appear to be too small for the planned technical concept and need to be enlarged or verified with detailed planning. A possible subdivision of the eastern part of construction site B into construction sections (predetermined thresholds) needs to be formulated. \\ The proportion of dedicated traffic space in the competition entry is above the average of all competition entries in the comparative analysis. \\ The reinforced concrete structure can be built to the required fire resistance of 90 minutes without any major problems. The explanatory report does not offer any fire protection compensation measures for the open-plan connections between the stories. Additional measures will be necessary here in order to obtain approval (e.g. fire extinguishing system). \\ Different materials, from transparent to translucent to opaque, are offered as façade infill and thus also as an option for controlling lighting and privacy in a differentiated way. \\ The goals in terms of sustainability, energy efficiency, and gray energy are positively ambitious, but require detailed verification. In particular, the choice of materials for the supporting structure and façade construction should be optimized with regard to the use of renewable raw materials (carbon sink) and/or the use of reused components. The extremely robust façade graphic seems well suited to filling the individual fields with recycled materials in order to minimize construction energy. The visual vibrancy already conceived in the design through variable façade materials would be enhanced by this.

Photo: Felicitas von Lutzau

The compatibility of the generously glazed and flexibly openable façades (sectional doors and folding systems) with the stringent requirements for the thermal envelope and airtight level needs further elaboration. \\ Overall, we assess the energy concept and the planned use of renewable energies positively. The available potential is exploited as much as possible. \\ To reduce the energy value of the building materials, suggestions are made for the use of recycled materials and products with a lower carbon content. \\ The sustainability concept appears well thought out and offers good prospects for leveraging further potential. \\ The State of Hessen’s requirements for achieving the minimal-energy standard can probably be met with the design as it stands. However, the high proportion of glass surfaces in the façade leads one to conclude that the building surfaces must be at least partially technically air-conditioned despite the good thermal insulation in summer. \\ The heat requirement is to be covered by geothermal energy, and the proposed concept appears plausible, but nevertheless raises questions about how to rate the existing remote heating links and thus the economic viability. \\ In addition to the grid connection, the electricity requirement is to be covered by a photovoltaic system. \\ With regard to the specified cost framework, the competition entry is above the average of all competition entries in the comparative cost analysis and above the value of the specifications from the “0” project. \\ Overall, the idea of developing the HfG as a little town around a leafy garden courtyard is perceived as very convincing. The jury particularly appreciates the fact that the designers have succeeded in developing a structure that appears as a robust single entity both in terms of its internal organization and its external impact.