The house. There it stands. Of course, you already knew it, you knew that it would be standing there, you had prepared yourself for it, and yet it still comes as a surprise. There stands an icon from recent architectural history that you knew only from drawings.

That experience is all the stronger because the design is so improbable. You know it as a conceptual project, an idea where things are brought into focus, a design for a home intended as an item for discussion. In sketches and photos of the model the design remained abstract. And now there it is, like a mirage in the Vinex desert, like a scene from a fairy tale, because the conceptual radicalism also turned the design into a caricature, a caprice, an object from a world where other rules apply, a simple child’s world where naivety still holds sway.

The house is tangible. And whoever goes inside discovers one beautiful room after another, well proportioned, pleasant to spend time in, real. A corridor as a corridor is supposed to be, with a beginning and an end, and sights along the way, a large studio in a quiet location and separated from the rest of the house, a practical combined kitchen and dining room, a spacious living room, thanks to a double curve in the wall and ceiling, with a majestic view of Paterswoldse Lake. The ritual pin-pricks that were latent in the design do not appear to have stood in the way of actually living in the house, as one might have feared.

Once you have recovered from the authenticity of the house, the question arises of what it is doing here. Who thinks up something like this? Designed in 1973 by a lecturer at the Cooper Union School of Architecture in New York for another Cooper Union lecturer, it is above all a didactic model. Why has it been built twenty-eight years later in Groningen, without a client who wanted to have it?

The answer is to be found in municipal politics. City marketing has become a serious business in Groningen ever since the municipal ‘Action Plan’ of 1988. An urban identity had to be launched and an image created of an up-to-date regional cultural centre.

The successes that have been reaped since then in the field of architecture and urban planning are considerable: the video pavilions of What a Wonderful World (with contributions from OMA, Bernard Tschumi, Zaha Hadid, Peter Eisenman and Coop Himmelblau, 1990), the city markers of Books of Groningen (with contributions from nine artists and architects under the supervision of Daniel Libeskind, 1990), the new Public Library building (designed by Giorgio Grassi, 1992), the new premises for the Groningen Museum (Alessandro Mendini, 1994), the recent Blue Moon festival (with Toyo Ito, Xaveer De Geyter, FOA, Space Group and Tony Fretton, 2001), to mention only the most striking events. Hejduk had been involved on several occasions. He was responsible for one of the city markers, The Tower of Cards, and in 1989 he produced a design for a block of flats on Reitemakersrijge in the city centre.

However, the funding failed to materialize, and the new building for the Academy of Architecture was erected on this site instead. All the same, there were regrets that Hejduk’s plan did not go ahead.

Furthermore, in the mid-1990s there was a search for a special building project to crown the large Hoornse Meer residential estate, where there was a good deal of experimentation with housing typologies. One of the city’s urban designers at the time was Thomas Muller, a former assistant of Hejduk. It was thus a combination of circumstances that led to the initiative to build Wall House 2, a design going back to 1973, on the most attractive site in Hoornse Meer. The reason why this particular project of Hejduk’s was chosen is not difficult to surmise: designed for a ‘real’ client, it was the most realistic of the designs in Hejduk’s portfolio. A developer and estate agent were brought in, and in 1995 the Groningen firm of architects Otonomo was approached to convert Hejduk’s sketches into a design that would be both technically and financially feasible.

The process seemed to run aground when no buyer for the house could be found, but was refloated again after Hejduk’s death in 2000. It was decided to build the house anyway, even if there was no buyer as yet. From a city marketing perspective, owning the only masterpiece of a dead architect naturally warrants a bit more risk-taking. The city authority now speaks of a ‘tribute to an exceptional architect’. A few months before the completion of the house a buyer appeared on the scene, so that the operation may now be regarded as an unqualified success.

It is interesting to consider some of the modifications proposed by Otonomo which have been implemented, because the Achilles’ heel of a conceptual design of this kind is, of course, the problem of putting it into practice. The first important intervention was in the spatial field. Almost all of the dimensions of the house have been enlarged by a factor of 1.2, not only to make the house more comfortable – perhaps that 20% can be seen as the decisive difference between a weekend house and a home – but also to make the space between the different elements of the house accessible for the contractor. The builders had to be able to work in the gaps between the wall and the different volumes without changing the proportions of the whole.

The choice of materials has also been modified by comparison with the original design. Hejduk had conceived the Wall House with a wooden skeleton, without insulation, and plastered inside and out. The frames were sketched as thin steel profiles. The house that has been built is insulated. Walls have been erected at different points in sand-lime brick for stability, and the frames are wooden for production reasons. Despite these modifications, the architects have tried to remain true to the original aim. The walls are still plastered inside and out and, seen from the outside, the wooden frames are concealed behind steel profiles (which may be used in the interior as well at a later stage).

A third crucial point is the way the concrete wall is experienced indoors, how the corridors cut through the wall at the three levels. Though desirable from a conceptual point of view, a ‘hard’ intersection here would have meant that the wall was accepted as a thermal bridge. Although that solution, which contravenes building regulations, would probably have been accepted by way of exception, Otonomo preferred to insulate and finish off the wall at these points. Since the wall is such a large surface, the cold down-draught would have been very great and would certainly have given rise to condensation problems detrimental to the pleasure of living there, the Groningen project architects argued. Ways will be found in the corridors to suggest that the cross-cut edges of the wall are in view.

Such choices are understandable. They domesticate the concept. The icon from architectural history has been measured, drawn in detail, and laid out on a field in Groningen. But it has lost nothing of its liveliness. It growls and fawns, attracts and repels, is touching in its unusual appearance, and commands respect for its undeniable force.