Factual Complex. Peter Zumthor’s Thermal Baths

Luigi Coccia

Mountain, stone, water, building in stone, building with stone, building into the mountain, building out of the mountain, being inside the mountain – our attempts to give this chain of words an architectural interpretation […] guided our design for the building and step by step gave it form. (Zumthor 1997, p. 56)

Thirty years have passed since Peter Zumthor carried out hits first studies for the Thermal Baths at Vals: an exemplary project, a love story between stone and water. It is a project that immediately aroused the admiration of the critics and much has been written about it. By making use of evocative images associated with its realisation, the work is analysed to understand the sense of the atmosphere repeatedly recalled by the author and effectively expressed in the shaping of the design. Why talking about this design again? The time for the design and realisation of the work (1991-1996) allowed the author to question himself on the creative process, to meditate on the relationship between theory and practice, and to find the words to make the design explicit. Architektur Denken and Atmosphäre are the titles of two books published in 1999 and 2006, respectively (Zumthor 1999, 2006). They contain reflections on the author’s way of understanding architecture, and on his passion for things that leads to things. The project for the Thermal Baths at Vals is an opportunity to explore the concept of the “factual complex” (Zumthor 2003, p. 26). developed by Peter Handke, often quoted by Peter Zumthor. It is a phrase associated with the recognition and experiencing of the site in terms of state of affairs, i.e., a condition in which things manifest themselves and contribute to the identification of a specific spatial context. Handke discusses fidelity to things, each time trying to turn the outcome of his observations into descriptions that can be experienced as faithfulness to the narrated place, and by renouncing all that is superfluous. Zumthor appreciates Handke’s effort to make texts and descriptions an integral part of the environment they refer to and, with the same approach, bases his research on acknowledging the factual complex. Drawings become instruments that reveal the essence of a place. They do not only describe the state of affairs, showing essential characteristics, but they also trigger an imaginative process. Imagination leads to concrete developments on the basis of the knowledge acquired, and to architectural reconfigurations on the basis of the original state of affairs. Conformity is considered as the adequacy of the form designed to the form experienced. It is conformity that particularly develops faithfulness to things, as posited by Handke. It is a search for a correspondence between architecture and reality.

Mountains, stones and water are physical entities identifying natural places; they are the same entities that have contributed to the formation and identification of artificial places and of the thermal baths architecture. The conformity of the work to the site is expressed by spatiality that can be likened to ground manipulation. It can also be compared to sophisticated excavations that produce habitable cavities absorbed in the context, not camouflaged. The facility does not show itself as a building complex but as a topography, i.e., as a geometric matrix organising internal and external space, materially homogeneous and made explicit by a tectonic fact.

The relationship between architecture and context is a controversial issue that has long been debated. It may have been eluded or little explored in recent architectural works. The issue is the background to the thesis on Critical Regionalism formulated by Kenneth Frampton in the early 1980s. His approach is oriented towards the valorisation of localistic aspects and site-specific factors that are in contrast with homologising trends – disruptive effects of globalisation. Frampton considers Regionalism as a critical concept rather than a style. He describes some works in which localistic aspects become evident. Thus, this critical investigation has a regionalist spirit and focuses on design research findings, not on architects’ profiles or theories. The reinterpretation of the project developed by Zumthor for the Thermal Baths at Vals is an opportunity to verify the correspondence of the work to the requirements expressed by Frampton. Above all, the aim is to evaluate the topicality of an experimental design that favours the development of a strong culture with an identity, which, nevertheless, welcomes universal techniques (Frampton 1984, p. 22).

The Thermal Baths at Vals: architecture and context

The baths complex is located in the northern end of a small village that stretches along the Vals valley in the canton of Grisons in Switzerland. The area is surrounded by hotels and condominiums built in the 1960s. They are rather anonymous building artefacts which deviate from the typical buildings of the original setting. Originally, the architectural landscape was characterised by small isolated houses similar to old stone barns with wooden roofs. This does not seem to attract Zumthor’s attention when focussing on the complex. No anthropic sign associated with the urban context is taken as a reference in the definition of the thermal establishment; yet the experimental design is not aimed at exploring an atopic space. The relationship with the context is revealed in the formulation of the following purpose: «the establishing of a special relationship with the mountain landscape, its natural power, geological substance and impressive topography» (Zumthor 1997, p. 56). Zumthor undertook research on a new thermal baths establishment on a site marked by orography and hydrography, at an altitude of more than 1,200 metres. The site was close to a spring of water flowing out from the ground at 30° C. He renounced the idea of integrating the new structure with the ones already existing that had been built in the immediate surroundings.

The experimental design took shape from the very first sketches. The black strokes obtained through the application of a soft material, a charcoal, traced the first planimetric patterns. The graphic technique evokes a design idea that expresses an intent: creating space through a topographic reconfiguration of the site. The drawings are essential, the graphic lines are strictly controlled, the colour fields are measured and localised. Dark blocks arranged on an orthogonal grid emerge against a light background and allude to a mass being cut. The square-shaped figures vary in size and are emphasised by blue segments traced around the perimeter. The segments allude to water infiltrations among the stereometrically shaped stone blocks. The experimental design continues with other drawings which use the same technique. Masses move away, they thicken or dissipate. The interstitial gaps appear compressed or dilated, and are marked by blue and yellow chromatic surfaces which refer to specific areas: water basins, rest areas and passageways. The sequence of drawings describes the progressive deepening of the experience, whereas the connection of words (mountains-stones-water) reveals the design choices.

The drawings explore the establishment place, but they also recall other places that are geographically and historically known and are impressed in people’s memory. They are «images of places that I know and that once impressed me», writes Zumthor, «images of ordinary or special places that I carry with me as inner vision of specific moods and qualities» (Zumthor 2003, p. 34). They are images of natural places shaped by water and wind or modelled by quarrying. They are marked by cutting phases that generate differences in height and levelling. They are geometrically marked by quarry faces. They are also images of places marked by the work of ancient civilisations, such as archaeological sites where the remains of massive walls are solidly anchored to the ground.

In its overall representation, the Thermal Baths at Vals project evokes a large porous stone placed on a sloping terrain. Upstream the volume disappears because it is completely absorbed into the soil, but downstream it emerges and shows its porosity to the outside world. Geography and history come together to create a soil architecture, and an artificial order of nature. This archaic environment resembles the temple foundations of the Roman times, such as the substructures of Latium sanctuaries: mighty masonry blocks as support bases for buildings. As the temples standing on the summit disappeared, the basement on the sloping terrain is what now remains of these sacred places. On the side facing the valley, the masonry blocks lose their forms, creating sequences of niches or cryptoporticus: resting or passage spaces covered by barrel vaults - cool places in summer and sheltered spaces in winter.

The Thermal Baths at Vals assimilate and process this ancient building principle, creating living spaces carved out of the thickness of the basement. «I wanted to build the walls of huge, solid blocks» asserts Zumthor,

I had imagined powerful rocks, and then even the largest ones turned out to be very small! I was absolutely disappointed. But walking around the quarry, I noticed stacks of thin slabs, trimmed for flooring. The quarry was full of such thin panels. I saw that such treatment of rock is the simplest and the easiest. I understood that, out of the thinnest elements possible, I needed to build the massiveness homogeneity of a block of rock. (Stec 2004, p. 10).

Zumthor defines his architecture as a geometric cave system (Zumthor 2007, p. 41), a sequence of empty spaces imaginarily carved in a stone block. Such spaces are made by arranging concrete walls covered by bands of local stone, the green gneiss, which resembles a geological concretion. The stones are placed horizontally with almost imperceptible gaps. «You cannot plan emptiness», writes Zumthor, «but you can draw its boundaries and so empty comes to life» (Stec 2004, p. 8). The experimental design becomes an exercise of creating space boundaries that not only delimit the environment but also direct movements by tracing paths and marking places of rest. This is evident in the drawings that anticipate imagined spatiality. Such spatiality aims at being concrete and gives voice to something that has not yet found a place in the real world. Architectural representations can thus make manifest the absence of real objects within a specific context and feed the desire for something concrete. In this way, «architectural drawings try to express as accurately as possible the aura of the building in its intended place» (Zumthor 2003, p. 11) without being influenced by external or accidental elements.

This helps understand the role of architectural portrayals in Zumthor’s research: only by absorbing the qualities of the desired object, do architectural portrayals anticipate the atmosphere that is created when the work is finished and becomes part of the concrete world. Such qualities arise from the interaction with the outer context. In order to acquire the qualities of the desired object, architectural portrayals do not have to resort to graphic virtuosity or realistic representations. «If they [architectural portrayals] lack ‘open patches’ where our imagination and curiosity about the reality of the drawing can penetrate the image, the portrayal itself becomes the object of our desire» (Zumthor 2003, p. 11). Zumthor insists on the need to always keep the desire alive for real objects, for what lies beyond representation, and argues that when the representation no longer evokes any promise, it vanishes.

The architectural portrayals created for the Thermal Baths at Vals are anything but realistic. They are synthetic and abstract, incisive and evocative, capable of conveying the idea that guides and directs the design choices. At the same time, the architectural portrayals show their formal development; they represent a description of the logical steps leading to the expected results. In this sense, architectural portrayals are premonitory: they anticipate what is about to come.

The sequence of the study sketches points out the founding principle of the thermal baths complex in the plan design and as a space creator. The architecture and the context coincide, as the one influences the other and vice-versa. Space is conceived at the base of the complex as it flows among large blocks and assumes a labyrinthine configuration. In some parts, it is closed and contained by the walls; it has an intimate and recondite character. In other parts, it is open, it escapes boundaries as it pervades the surrounding area, favouring exploration and interconnections. Zumthor argues that architecture knows two fundamental possibilities of spatial creation: «the closed architectural body that isolates space within itself, and the open body that embraces an area of space that is connected with the endless continuum» (Zumthor 2003, p. 16).

In the Thermal Baths at Vals, the two spatial concepts coexist: the changing rooms, the hot and the cold baths, the sauna and the Turkish shower, but also the “flower bath” and the “sounding stone”, which are all small habitable caves. They are isolated “closed bodies” located on a plane marked by continuous altimetric variations connected by stairs and ramps which, in addition to showing the way, shape the water pools and accompany the progressive immersion of the body. The architectural portrayals envisage all this and describe the trajectories of the possible crossings of the thermal space. Unidirectional arrows invite the visitor to follow a solitary path; bidirectional arrows favour encounters. The space walked through is compressed or dilated depending on the trajectory followed. In passing from one room to another, the number of steps is never the same; the floor levels, the dimensions of the spaces and their heights vary, just as the width or the depth of the passages. Along the solitary paths, marked by small staircases cut out between the wall blocks, the vision field is limited. Along the other paths, marked by ramps and widening, the vision field expands, allowing a more extensive perception of space in its planimetry and altimetry. This conveys a sense of discovery; the pleasure of moving through an unknown place or exploring a natural space. «Let me give you an example, in connection with some thermal baths we built» writes Zumthor, «It was incredibly important for us to induce a sense of freedom of movement, a milieu for strolling, a mood that had less to do with directing people than seducing them» (Zumthor 2007, p. 42).

Seamlessly, the interior space extends outwards, generating “open bodies”, such as islands and terraces built from the extensions of the walking surface. They emerge from the water of basins and pools, appearing as fluid intrusions into the monolith. Local green stones cover the walls made of thin slabs. The interior and exterior flooring is made of slabs of different sizes and is also patterned with green stones. It conveys the idea of being cut horizontally and, hence, of being larger in size. From an architectural point of view, the arrangement of the stones produces a monolithic impression: not only are the walking surfaces made of stone, but also the floors of the pools, the stairs, the seats and the door thresholds. Everything is developed according to the same principle of matter layering.

The predominantly introverted space acquires an extroverted character in the transition from indoors to outdoors when crossing the thresholds as points of interaction between architecture and landscape. The space opens up towards the overlooking mountain and creates a physical and visual contact with the surrounding nature.

The two spatial concepts explored by Zumthor in designing the thermal baths are further enhanced by light, either natural or artificial, which produces shadows on the stone blocks and reflections on water. In addition to light, sound contributes to enhancing the atmosphere of the place, as the sound of water against the walls during ablutions. Visitors walk through interior caves to reach the ones outside and are guided by the light coming from above through narrow slits – gaps in the roof slabs. Light and sound perceptions vary greatly according to space geometric features and their specific uses. The light and sound experience changes from the public central pool, where natural light from above and from the side windows is more intense and noise is more diffuse, to the warmer water pool, which is enclosed in a narrow but high space resembling a cave. Here the light is artificial; it comes from the bottom of the pool, it is filtered through the water and diffused into the steam-saturated air. The stone walls marking the space limits have no openings, so the sound produced inside is absorbed and creates evocative echoes, suitable for meditation. The darkness of the interior caves is contrasted by the light that floods from the open spaces and goes around the outdoor pool. Darkness is also contrasted by the open but covered spaces in the wall blocks that, going downward, mark the edges of the monolith set in the ground

The Thermal Baths at Vals: regionalist architecture

In 1980, Kennet Frampton published Modern Architecture: a critical History and laid the foundations for reflections on the development of regionalist architecture. Insights into the subject were later provided in a number of essays published in 1983 and in an additional chapter to his History of Modern Architecture entitled Critical Regionalism: Modern Architecture and Cultural Identity, published in Italy in 1986. At the beginning of the fifth chapter of his book, Frampton quotes Paul Ricoeur at length on the phenomenon of universalization. Universalization leads to an advancement of mankind but, at the same time, it allows the destruction of the «creative nucleus of great civilizations and great cultures» around which life takes shape and meaning. In this way, it becomes the «ethical and mythical nucleus of mankind». «We have the feeling that this single world civilization at the same time exerts a sort of attrition or wearing away at the expense of the cultural resources which have made the great civilization of the past», asserts the French philosopher, arguing that participation in modern civilisation does not imply the erasure of the entire cultural past. Thus, according to Ricouer, the challenge is «how to become modern and return to the origins; how to revive an ancient, dormant civilization and be part of a universal civilization» (Frampton 1986, p. 371).

The answer to the questions raised by Paul Ricoeur can be searched in the theory posited by Kennet Frampton on Critical Regionalism. The concept of region is associated with a spatial sphere where it is possible to recognise a living and building culture passed down from generation to generation. The concept of regionalism, instead, refers to a contemporary design attitude which does not subdue to globalisation trends – often shaped in homologated and conformist forms. Regionalism pursues a critical intervention approach that, thanks to innovative building techniques, experiments with forms that are capable of rediscovering and enhancing the qualities of places and of specific identities. This is the ability to interact with cultural resources, and it is often intrinsic in places or in the singular intertwining of natural and artificial landscape. Such ability allows the development of a design methodology that takes on a universal value, thus participating in modern civilisation. Critical Regionalism is not the expression of a vernacular architecture, or a spontaneous work resulting from the interaction among climate, culture, myth and craft. On the contrary, as Frampton argues, it identifies the newly created regional schools whose main ambition is to mirror and address the building blocks they are composed of. In pursuing this objective, Critical Regionalism experiments with an architecture that is rooted in modern tradition but is also connected with the geographical and cultural context. Thus, it proposes a progressive approach in design by mediating between localism and globalism.

The design experience supports the theory developed by Frampton in Critical Regionalism in which he formulates a list of characters or rather, as he specifies, “attitudes” recurring in a “critical conception”. Starting from the enunciation of seven points in the fifth chapter of the History of Modern Architecture entitled Critical Regionalism: Modern Architecture and Cultural Identity, Peter Zumthor’s design for the Thermal Baths at Vals is now examined. The characteristics of such design are analysed in light of the theory outlined by Kennet Frampton.

The first point to analyse concerns the relationship with modernity. While opposing modernisation, Critical Regionalism «refuses to abandon the emancipatory and progressive aspects of modern architectural legacy», (Frampton 1986, p. 386) but moves away from normative optimisation, utopia and large-scale exploration. The thermal baths designed by Zumthor are a small-scale experimentation that looks at the past with a thoroughly modern spirit, and radically transforms it. There is a fascinating mix of tradition and innovation in the design. Zumthor uses materials based on the local culture and applies contemporary building techniques that draw on the modernist experience. Elements of the modernist experience are found in the architectural portrayals; from the dealing with space to serial building methods. In this way, he demonstrates that the craft aspect, as acknowledged by some critics, actually plays a marginal role.

The second point that distinguishes Critical Regionalism is that it does not focus on isolated elements, but it emphasizes the territory. In this regard, Frampton defines “place-form” as the sphere where the building action begins and ends. Experimenting with an architecture that starts from things and returns to things is Zumthor’s stated aim, which is also put into practice. The alpine context, made explicit by the word chain “mountains, stones, water”, confirms its key role in the built work. It is architectural spatiality that manifests itself not as an establishment, but as a context artificial fragment. Zumthor is attracted to buildings that give the impression of being solidly anchored to the ground and are an integral part of the environment they belong to. The thermal baths complex is the realisation of such an idea; it is a refined integration of architecture and context, a “place-form” that can be likened to those works that apparently say: «I am as you see me and I belong here» (Zumthor 2003, p. 14).

The third point is as follows: «Critical Regionalism favours the realisation of architecture as a tectonic fact rather than the reduction of the built environment to a series of ill-sorted scenographic episodes» (Frampton 1986, p. 387). Tectonics is a building art that keeps together structure, material and spatial perception. Tectonics characterises the Thermal Baths at Vals, conceived by Zumthor as a “geometric cave system”. It is a complex made of local stones: the green gneiss. The green gneiss gives the thermal baths architecture the image of a geological concretion thanks to its extraordinary framework. The tectonic idea is reinforced by anchoring the complex to the ground, and in the aim to place the new thermal bath in a particular relationship with the primal strength and geological substance of the mountain scenery and the impressive relief of the topography (Steiner 1997, p. 27).

Ultimately, the work is the result of an interaction with the specificity of the context; it is absorbed but not camouflaged in the place, it clearly shows its artificiality but renounces a purely scenographic manifestation.

The fourth point highlights the local nature of the work: Critical Regionalism emphasises certain site-specific factors. As mentioned, in the design of the Thermal Baths at Vals, the topography is considered as a three-dimensional matrix the complex fits in. In emphasising the specificity of the site, Frampton also considers local light as «the primary agent by which the volume and the tectonic value of the work are revealed» (Frampton 1986, p. 387).

Light, predominantly artificial, characterises interior spaces: «in a cave, artificial light must be used», writes Friedrich Achleitner, «and the lighting methods used by Zumthor recall distant experiences of the Alpine world and the oldest memories of light in the mountains» (Achleitner 1997, p. 61). From the inside to the outside, the transition from half-light to full-light takes place. The “geometric cave system” obtained through excavations in the large monolith anchored to the ground is transformed into terraces and patios projecting towards the landscape. The different light sources emphasise the value of the environment. The light, either natural or artificial, contributes to the creation and perception of space.

The fifth point of Critical Regionalism revolves around the perception of space. Frampton believes that the qualities of an environment should be experienced not only visually but also tactilely. He describes the changing light intensity of certain environments; heat and cold sensations; the different degrees of humidity; air movement; the presence of odours, and the propagation of sound in geometrically different environments. These themes recur in the research developed by Peter Zumthor and lead to the definition of the concept of “atmosphere”. Recollections, images and ideas embodied in personal memory guide the design process, leading to the realisation of what the architect likes to call “atmosphere”. He often describes certain places associated with his childhood in an accurate and passionate way: «I remember the sound of gravel under my feet, the soft gleam of the waxed oak staircase, I can hear the heavy front door closing behind me as I walk along the dark corridor and enter the kitchen» (Zumthor 2003, p. 7).

Zumthor questions himself on the “real magic” and asks himself the following: «can I achieve that, as an architect, an atmosphere like that, its intensity, its mood. And if so, how do I go about it?» (Zumthor 2007, p. 17).

The design of the Thermal Baths at Vals can be considered a successful experiment.

In the sixth point, Frampton draws attention to the concept of “local vernacular”, believing that Critical Regionalism can occasionally include «vernacular elements as disjunctive episodes within the whole» (Frampton 1986, p. 387). The form abstraction that characterises the thermal baths designed by Zumthor is so dominant that it leaves little room for vernacular elements. Undoubtedly, the texture of the stone of the massive walls recalls ancient retaining walls in mountain areas. However, the building technique is so refined and innovative that the traditional dry-stone walls are transformed into the so-called «Vals composite wall», where concrete adheres monolithically to thin slightly staggered stone slabs, thus resembling a fabric. This is an admirable reinterpretation of the dry-stone wall which pervades the architectural layout of the complex, and cannot be considered “vernacular”. Other elements could be brought into this category. They appear as detached since they contrast with the dominant material – the green gneiss that covers the entire monolith. Thin pipes from where water gushes out are placed on the retaining walls at regular intervals; thin circular section railings are found on the edges of terraces and loggias, and elegant doors lead to therapy rooms. These are building elements made of an ancient material, brass, an oxidizable alloy composed of copper and zinc. The dark wood panelling used in the changing rooms is also unrelated to the whole environment. Techniques passed onto Zumthor by his father during his youthful apprenticeship as a cabinet-maker also emerge from the panelling. All these elements are not easily matched with the idea of vernacular, although they contrast with the dominant appearance of the complex and are evocative of ancient local traditions. Eventually, by analysing the whole complex, it is possible to notice some tension «in this regard, it tends towards the paradoxical creation of regionally based world culture, almost as though this were a precondition for achieving a relevant form of contemporary practice» (Frampton 1986, p. 387).

The seventh and final point highlights that Critical Regionalism tends to thrive in cultural realities that escape the tension of universal civilisation. Also, Critical Regionalism eschews the subdued position imposed by the dominant global culture and by those dependent on or dominated by it. A design approach emerges from cultural gaps; it valorises places, history and tradition. In this way, it triggers an intellectual reaction to globalisation. The sensitivity demonstrated by Zumthor in the design of the Thermal Baths in Vals is an opportunity to emphasise a design methodology that goes beyond the specificity of the local context. His critical attitude escapes an «optimising tension» and assumes a universal value. The following statement by the architect is very effective as it addresses contemporary architectural research, singularity and universality, local and global dimensions:

When I come across a building that has developed a special presence in connection with the place it stand in, I sometimes feel that it is imbued with an inner tension that refers to something over and above the place itself. It seems to be part of the essence of its place, and at the same time it speaks of the world as a whole. When an architectural design draws solely from tradition and only repeats the dictates of its site, I sense a lack of genuine concern with the world and the emanations of contemporary life. If a work of architecture speaks only of contemporary trends and sophisticated visions without triggering vibrations in its place, this work is not anchored in its site, and I miss the specific gravity of the ground it stands on. (Zumthor 2003, p. 34)

Peter Zumthor opened his office in 1979 and his first important works date back to the mid-1980s. His works do not appear in the chapter on Critical Regionalism that Kennet Frampton added to the second edition of his Modern Archiecture: a critical History published in 1985. In 2012, Kennet Frampton visited the office of the “mountain man”, as Zumthor is called in Haldenstein, a remote village in the Swiss canton of Graubünden surrounded by mountains, where he lives and works. The documentary The Practice of Architecture: Visiting Peter Zumthor (2012), directed by Michael Blackwood focuses on an interview Frampton had with Zumthor. Moving between models and drawings, starting with his early pioneering works, including the Thermal Baths at Vals, the architect dwells on his bent for minimalism, his appreciation of landscape, light and materials, and his theory on his extraordinarily precise style.

Peter Zumthor’s design experience in recent years can be seen as the confirmation of the thesis put forward by Kennet Frampton in the mid-1980s in Critical Regionalism: Modern Architecture and Cultural Identity. While well rooted and incorporating the specificities of the context, his works are capable of conveying universal content, and can ultimately be considered the expression of a fertile dialogue between a place and the world.

Switzerland, with its intricate linguistic boundaries and its tradition of cosmopolitanism, has always displayed strong regionalism tendencies. The cantonal principle of admission and exclusion has always favored extremely dense forms of expression, with the canton favouring local culture and the Federation facilitating the penetration and assimilation of foreign ideas. (Frampton 1986, p. 380)


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