Roger Boltshauser: There are spaces that work and spaces that don't work, those that are intended for people and those that are less so – just as there are comfortable and uncomfortable chairs. As a designer you should at least know what a comfortable chair is, and if you then go ahead and make an uncomfortable one it is your free decision. An architect should, for instance, be able to assess what makes a facade public or how to place and design the entrance of a building for it to be instinctively findable.
Today one quickly creates very complex geometries without really being able to control their effect. Architectural spatial principles are independent of style. Buildings don't always have to be like blocks, as is the case with mine so far; they can also be more freely formed. The more complex a form is, however, the more challenging it gets to master it; that requires a lot of experience. Le Corbusier, for example, was continually developing and only found his way to freer forms late in life. Ronchamp is a precise spatial disposition in this sense: free curves, but they refer to their surroundings. This is lacking in most of today's 'dynamic' buildings.
In our accelerated society, the problems have changed but the way we move on foot in an urban space and perceive it has stayed almost the same for the last 3000 years. The old squares are more in demand than ever. Also with a view to ecological issues, we simply can't afford the current urban sprawl and mobility any more. Spatially well-designed density, squares with high user amenity are more in demand today than ever.
The domes of Adliswil broaden part of the space under the massive roof of the recess area and thus differentiate it, also by means of the light seeping in through the glass bricks. The mud walls of the Sihlhölzli outbuildings carry the natural space of the neighbouring river into the heritage ensemble of the sports grounds. With the house in Schlins, which was built of earth that was rammed, fired or treated in any one of a wide variety of ways, the choice of material was a given: the client, Martin Rauch, is one of Europe's leading specialists in earthen construction. His house is a kind of experimental setup and showpiece. There I interpreted the properties and possibilities of the material's various manifestations in spatial terms. Quite apart from that, the house is exemplary as sustainable architecture because we obtained the building material for the whole house almost entirely from the foundation pit.
Unfortunately one rarely talks about types today, but I think that typologies still have great relevance. I am amazed when the full range of building types wins prizes in a competition, as though it didn't matter which of them is used: perimeter block, rows, and the first prize perhaps to a solitaire because it offers the best facades. Why do they not look for the right type for a specific site? I have the feeling we are no longer sure what is actually the point.
[Indoor spaces] are the important opposite pole to the city, to the outdoor space. The transitions between outdoors and indoors are of central importance in a building. In the Rauch House you experience the landscape through the way the space unfolds: the two-storey studio with a north window in the slope, the slightly flowing spatial figure next to it that seeks out very particular views across three, four windows – indoors and outdoors are interlinked.
Axel Simon: Your building masses so far have been quite simple, chunky blocks. Can you explain this preference?
RB: I haven't progressed any further yet. Even with these relatively simple volumes, generating tension is very challenging. When I think of the Greek temples – dissolved but block-like building masses, in which the lines curve and incline subtly in order to adjust the perception of the volumes to make them seem more corporeal and pure – then I feel quite modest in my means. Simply investigating the volume, I haven't finished that yet. This precise calibration of masses is an adjustment process; it takes a lot of work before something begins to change. I can imagine making more complex forms some day but I am not ready yet. Mastering a simple block is already quite a lot.
AS: Your persistent work on a few principles and topics is also apparent in the fact that certain elements keep turning up in your buildings.
RB: Yes. I keep building these skylight boxes, for example, or the same window types, though with variations. Nowadays everything has to be fresh and hip – for me every commission is a chance to develop things further. I feel enormous pleasure; it suits me. After all, they also say Picasso only painted five pictures, and the rest are variations on these five.