Red shift.

Burkhalter & Sumi's modest kindergarten in an Austrian suburb explores the relationship between whole and part through simple massing and the use of colour.

In its bland Austrian suburban context Burkhalter & Sumi's red kindergarten, as it is locally known, becomes a landmark merely through its colour and size. The apparently simple massing and the choice of a bold red close to that of a long-popular line of wooden toys evokes winsome memories of children's building blocks. But it quickly and naggingly insists on oscillating between being a whole and a composition of parts, asserting perceptual and formal ambiguities and a complexity characteristic of Burkhalter & Sumi's work (AR January 1997).

At the ground floor the entrance splits the building in two, with the kindergarten to one side and an infant care station with three small flats above to the other. Z-shaped circulation divides the kindergarten along its long axis and reflects a more complex composition, with the tension between whole and part reinforced through fenestration and the use of colour. At upper level, the identical tall volumes housing flats and playrooms touch at only a single point (though in the continuous figure of a Mobius strip), and are then separated perceptually. A lower, one-storey mass sits next to the entrance. This is tied to the block behind it in plan and by the orientation of its windows, and also to the mass beside it by colour' and location.

Burkhalter & Sumi limit themselves to one size of window, but this is used both vertically like traditional french windows and horizontally like a Modernist ribbon. By setting the windows flush to the exterior cladding they avoid what they describe as the violence of cutting a hole in a wooden skin. The subsequent lack of shadow strengthens the integrity of the masses and helps make the elevations powerfully graphic and even playful. While not the simplest to detail, this building is another in a series that draws on the architects' research into contemporary timber construction. The number and proximity of the windows on the exterior wall of the playrooms, for example, denies typical wood construction and reduces the wall to a plane balanced between transparent and opaque.

The ground floor of the kindergarten is divided by a spacious, skylit corridor animated by a rhythm of ceiling joists. To the south are three double-height playrooms with balconies, and cloakrooms elongated to lead directly outside. To the north of the corridor are two exercise and nap rooms. Interiors are warm and calm, with walls clad in large birch plywood sheets and floors cork. In contrast to these natural finishes, the red is brought inside as another layer on sliding doors, lamps, columns, and window frames to delightful and surprisingly gentle effect. Colour is used to unite disparate formal, material, functional elements and confirms the architects' work as rigorous without being pedantic.

The fertile interaction of colour, construction and proportion is especially apparent in the playground. The space is enclosed by two walls of the same height which meet at right angles and are wrapped in white for a vaguely public feel. The siting of the pergola catches the edges of the masses while letting the axis of the entrance slip by, thus gently defining another volume. The pergola functions as a summary of the building, condensing the themes of massing, colour, verticality and horizontality. It also draws attention to the four indigenous birch trees which mark the entrance. The passage from the entrance transforms the pergola into a kind of primitive hut, mediating between the raw material of the trees and the sophistication of the building's timber construction.

Architects Burkhalter & Sumi, Zurich

Project team Andrea Bassi 

Structural engineer Ingo Gehrer, Hochst

Landscape architect Stockli, Kineast & Koppel

Photographs Heinrich Helfenstein