RAINBOW ROOMS.

A research centre in Berlin for optics announces its functions by ingenious use of colour.

Sauerbruch Hutton's Photonics Centre in an industrial suburb of Berlin has been quite extensively published, but that was no reason for it not to be recognized in the ar+d awards. Fundamentally, it is a couple of curvy glass buildings set within a large, calm, three-sided court defined by reticent 1960s work. The architects argue that the forms of the new blocks are determined by specific site conditions, and by the desire to reduce the overall mass of the new work.

Of the two buildings, the larger has quite a deep plan, in the middle of which is a central spine which runs along the whole length. Within this are the daylight-free areas of the optical laboratories. Between spine and perimeter are lettable units which vary in size according to the perimeter's curve. The smaller building contains a simple 7.5m-high flexible production space for large-scale experiments.

Structurally, the buildings are quite different: the big, three-storey one is of concrete, with composite steel and concrete floors and exposed zinc-coated permanent shuttering between U-shaped beams. The small building has a simple steel structure with a concrete roof slab. Columns are set back from the perimeter and the double skin is stiffened by extruded aluminium wind-bracing posts. Round the big building, the facade is rather more complex, with a 700mm cavity between the two layers of glass. Paired columns divide the cavity into alternating zones of fresh and stale air. A system of sash windows allows users to vary their intake of outside air. Such arrangements are now becoming commonplace, if not exactly mandatory, in new German office buildings, but the system here is particularly ingenious, simple and economic. In the cavities of both buildings are adjustable blinds which are coloured according to the spectrum - this is after all a centre of research into light, and the changing patterns of colour of the perimeter are intended to make the fact clear.

We were all impressed by the sophistication of construction and environmental control. But some of us had strong reservations about the amoebic and apparently arbitrary nature of the planning.

ARCHITECT

SAUERBRUCH HUTTON