Concrete design in wood
KARLSRUHE (DE) - Karlsruhe can consider itself lucky that important institutions such as the Federal Constitutional Court and the universities are located in the middle of the city, contributing to a degree of urbanity that in other comparable cities has to be painstakingly resuscitated. Jürgen Mayer H.'s new refectory for the College of Higher Education and the Teacher Training College, centrally located near the famous Schlosspark, meets town-planning and, of course, functional needs, but also fulfils a representative role. With its straight-edged but non-rectangular ground plan, the building's appearance, pastel yellow on the outside and lime green on the inside, is certainly out of the ordinary. In summer, however, it is concealed along two sides behind tall, broad-leaved trees.
The windows sit in the facade like flattened amoebas; inclined supports and diagonal girders seem to have jumped straight from the computer screen into reality. But in its finished form, the refectory does not quite live up to the organic character suggested in the design, published in A10 #3. The ground plan makes a surprisingly conventional impression. There are two entrances, one on the street and one at the side. Inside, the eating area extends over two storeys and a gallery right up to the roof terrace. The main facade on Moltkestrasse features an intermediate zone in the form of an arcade-like walkway. On the north side, where a new sports field and playground for children is being built, are the kitchen, the cold store and the offices.
In this upbeat pop architecture there is no sense of any ethical obligation to produce 'good construction'. On the contrary: in the competition version, the refectory was to be built in bare concrete. This proved to be too expensive, and the outer skin now consists of a prefabricated veneered plywood box-structure. The boxes, 30- to 60-cm-thick and filled with insulating foam, are made of 88-mm-thick wooden panels, some of them curved. The wood is protected by a layer of hot-sprayed, breathable polyurethane to which a UV-resistant coating has been applied. The core structure was built using concrete up to the top of the ground floor, and then switching to wood. Although the roof girders are not positioned diagonally as originally planned, the architect simulates this effect as seen from below: a reminder of a load-bearing structure that was never brought to bear.
The upper storey opens onto a small roof terrace. The roof surface itself is slippery smooth and is treated as fifth facade, with some sections being planted. As in his town hall for Ostfildern/Scharnhausen, the Karlsruhe refectory again shows Jürgen Mayer H. distinctive taste with respect to materials and the shape of spaces, which in this case feel surprisingly compatible with the city.
September | 2006 | Germany | Ursula Baus