QUARRY QUINTET.

On a forgotten site in Kaiserslautern, near the football stadium, this small terrace of houses shows the variety and ecological responsiveness that can be achieved with client collaboration and semi-industrial building methods.

Betzenberg is part of Kaiserslautern in the Rheinland not far west of Mannheim. Fabled for its football team, the city has a tight, if dowdy, centre surrounded by loose suburbs. On the fringe of the core, just south of the railway station and west of the town sports stadium, is an abandoned quarry which in its time produced the red sandstone from which many of Kaiserslautern's nineteenth-century buildings were made. Over the years, the quarry became overgrown and now there are mature trees down there at the bottom of the valley.

Five families managed to get the place as a site for houses. Clients and architects Butz Dujmovic Schanne Urig bravely decided to arrange the five in a terrace -- a single bold move which released most of the site for a communal garden: think of conventional suburban developments (of which there are so many in Kaiserslautern, and how they would have eaten up the space with meaningless and largely unusable small gardens). In fact, by putting the terrace close to the small sandstone cliff in the north-east corner of the quarry bottom, most of the site has been released as a communal meadow surrounded by a backdrop of woodland. Access is from the north-east, via a route which runs under the railway tracks that leads to parking places, set under the cliff a short distance away from the houses.

The terrace is in the sunniest part of the site, so the whole south-west front was given the same treatment: standard sliding glass panels allow all the houses to look over the meadow. Horizontal galvanized steel grids suspended from the structure reduce heat gain in summer. On the other side of the terrace, the houses have more individuality. The whole of this side is clad in larch laths, penetrated by entrance doors and strips of windows that reflect the arrangements of the individual families. Between terrace and cliff on this side is a play street for small children which also doubles as access for emergency vehicles. Gradually, the larch on the north-east wall and on the almost imperforate ends of the terrace will weather grey, and from the top of the quarry the result is intended to be almost geological, with the turf-planted roof adding to the effect.

Grey continues inside the houses, where fairfaced concrete walls and floor slabs are exposed. They form the fundamental structure, making a rigid egg-crate like arrangement in which the houses are separated by party walls, each with a thin sound-reducing cavity between paired vertical concrete planes. The horizontal planes, the floors, are carved into and cut back to allow for stairwells and voids in which there is a considerable variation, for each plan is different and highly tailored for its family. All the houses are pretty minimal, but House Two (second from east) is the most minimal of all; here, for instance, partitions round the bathroom are reduced to no more than sheets of translucent glass. In all the houses, suspended straight-flight stairs have treads and risers made of continuous sheets of folded steel with flat steel stringers. But only in House Two are balustrades completely eliminated.

Throughout, there is an austere, economical yet not ungentle intelligence. For instance, the brise-soleil on the south-west front also serve as little balconies; the concrete of the party walls is projected across the deck to provide a degree of privacy for each house. The self-maintaining turf roof is heavily insulated, and its surplus water is collected and used to irrigate the meadow rather than being pumped up into the town drain. On the roof are solar collectors to reduce the cost of hot water.

At human level, economical planning and standardization of parts has allowed quite large floor areas and a good deal of freedom in planning. But clearly, though each house may have its particular personality, the five households have to strike an unusual balance between individual and communal. Clearly the delicate equilibrium works well at the moment; it will be interesting to see what happens over time.

Architect

AV 1 Architekten:

Butz Dujmovic Schanne urig

http:/www.avlarchitekten.de

Photographs

Michael Heinrich