BUILD TOGETHER – LEARN TOGETHER
Participatory Student Building Project Spinelli Mannheim

Photography: Yannick Wegner, Mannheim

Due to bureaucratic procedures, refugees arriving in Germany are condemned to sustain a long period of passiveness. At the refugee camp on the area of the former American Spinelli Barracks in Mannheim they are well provided with the bare essentials but the immediate area is quite desolate and lacking of quality common spaces.

This is when the Spinelli project came into being. 18 students from the Department of Architecture at the University of Kaiserslautern built a community centre together with 25 refugees and local building companies. The residents at the preliminary reception centre had the opportunity to actively shape their environment and create a quality place for common or individual use. The refugees improved their knowledge of the German language, experienced conditions and working standards in Germany and acquired new skills which will be useful even if they can’t stay in Germany on a permanent basis. The architecture students took the opportunity to make an active and positive contribution to the refugee crisis. They were able to have their own design executed for the first time. As expectant architects they contribute expertise that may appear luxurious in a refugee camp in the first place but upon closer inspection are even more important: creating pleasant places and high-quality architecture. They are learning to compare their ideas with very concrete necessities and to reflect their abstract planning in the implementation. Digital drawings materialized on the building site within weeks.

First of all a room schedule and general conditions were worked out together with the refugees.
The students then individually produced designs under the supervision of the departments of Tectonics in Timber Construction (Jun.Prof. Stefan Krötsch), Structure and Material (Prof. Jürgen Graf) and Digital Tools (Jun.Prof. Andreas Kretzer). Five designs were selected to be elaborated in groups. After two months the work was presented to a jury of representatives of the client and the involved departments and one design was chosen for execution.

The rest of the extremely intensive summer semester was spent by the whole group preparing permission and execution drawings, supporting structural planning, visualizations, scheduling and cost planning. Thanks to the support of the city administration of Mannheim it was possible to achieve the necessary building permissions and organize public contract award processes until beginning of construction in mid-August. From that time on the students worked, ate and lived together with the refugees in the Spinelli Barracks until the end of October. This resulted in an intensive working atmosphere and very positive group dynamics in the building team. The refugees felt accepted and valued in their situation. Together they built the timber construction for the approximately 500 square meter building complex under supervision of the participating teachers. Only groundwork and roofing were made by local contractors. Facing an extension of construction schedule from 6 to 12 weeks due to various unfavorable circumstances, the student group decided to forego holidays and other plans and to carry on working until the start of the new semester in November. After completing final works the building was officially handed over to the refugees at the end of November.

The chosen design by Sandra Gressung, Sascha Ritschel and Tobias Vogel impressively succeeds in resolving the difficult urban situation and allows future users to easily identify with the building. Interior and exterior rooms are either linked or separated in a carefully created succession of spaces. The walls of the main building continue northwards to the exterior revealing two yards with very different characters. An enclosed space with covered niches facing east and south serves as an introverted garden, an area of retreat and silence. Seating areas facing south and west accommodate a large yard for events which opens up invitingly westwards to the main road of the camp. The mayor common room faces this yard and can be used as either stage or auditorium. Two additional storerooms can be used as a kiosk and workshop in the future. The building offers a great variety of spaces within a very small area, making its users feel at home in their own way. Covered rooms and enclosed yards are shielded from the dull surroundings and focus to the tree-lined road and open fields west of the camp. Structural elements, wall and ceiling surfaces, flooring and furnishings are made of untreated timber. Its intimate warmth, aesthetics and haptics acts as invitation.

In order to build structural elements like walls and roofs in only six weeks, large-format components were prefabricated in an unoccupied hangar of the former military facility. This way it was possible to protect the structure from moisture during processing and to assemble elements on site quickly and with high precision. The light weight of timber allowed the transport of large pieces by simple means. Therefore the students designed wooden dollies which also allowed easy and safe assembling large wall elements. Turned at a 90° angle, the dollies work as scaffoldings.
The walls are timber frame components made of squared timber planked with cross laminated timber panels and cladded with back-ventilated boards of Douglas fir. The roof structure of timber-beams are planked with cross laminated timber panels and sealed with bituminous sheeting.
Light weight of the buildings construction allowed to reduce foundations to few singular footings (1,0m x 0,50m) in a grid of 3,50m by using the four meter high walls as trusses. This way costs for foundations were as much reduced to a minimum as the negative ecological impact of concrete.
Along the 22 meter long north wall, the economization of the foundations is taken to extremes. Seating niches integrated into the wall are protected from the rain by a two meter wide canopy and partitions between the niches. The partitions don’t need foundations. The structure is solely footed along the back wall and only held up by two walls on the sides an the one in between using the roof as horizontal girder.

In order to reduce building costs and to make good use of the many available helping hands, large machinery such as cranes or transport vehicles wasn’t employed. Instead simple and material saving but labour-intensive constructions and building processes were used. Walls and girders made of simple battens are symbolic of this: Douglas fir battens 3 by 5 cm are screwed together to a grid of five vertically and diagonally arranged layers and build a highly efficient supporting structure. Due to its low transverse tensile strength and the risk of cracking in the screwed fastenings of the interconnected battens associated with this, the anisotropic material wood only allows low force transmissions. The grid walls compensate for this phenomenon by the multitude of supportive battens and due to the fact that force transmission from one batten to the next is not necessary.

In contrast to the grid walls, the load-bearing performance of both the 7 and 14,5 meter grid girders is complex. While the walls carry loads in a directly vertical, within the grid trusses vertical have to be guided from all over the girder to the bearing. This distribution of forces leads to a summation of forces towards the bearing so few stable elements at the connections would have to transfer large forces. That is why the construction of the small grid truss uses slightly stronger compression diagonals of 4 x 5 cm, which are connected by face staggered joints with an upper and lower beam. The considerably higher forces of the large girder no longer allowed load-bearing grid structures. However in order to create an architecturally uniform image of trusses and walls made of battens, filigree batten are cladding and infilling a trussed girder structure. Compression diagonals 8 by 20 cm transmit large forces via face staggered joints through simple contact pressure, complemented by vertical tensile bars of threaded rod.

The grid constructions give the building its unique architectural expression. The ornamental structure with its varied play of light is recognized by the refugees as a reminder of oriental ornaments and as an inviting gesture of identification in a foreign place.