1.0 “…Mountain, stone, water – building in the stone, building with stone, into the mountain, building out of the mountain, being inside the mountain – how can the implications and the sensuality in the association of these words be interpreted, architecturally? The whole concept was designed by following up these questions; so that it all took form step by step…” – The Architect, Peter Zumthor.Therme Vals sits in the hillside as if a natural rock outcropping. Constructed from local stone, it grows from the flanks of the mountainside. One of the primary materials used in the building is gneiss, a rock formed through metamorphic processes, where high pressure and temperature under the earth’s crust force surrounding rocks together to create a layered effect. “The load-bearing composite structure of the baths consists of solid walls of concrete and thin slabs of Vals gneiss broken and cut to size in the quarry just behind the village. The thermal water which comes from the mountain just behind the baths has a temperature of 30°C.” (www.pritzkerprize.com)This material is very appropriate as it reflects the way the water of the baths is heated. The baths were built over a thermal spring, with the spring water filling the baths naturally heated through geothermal heating.During the day, light energy from the sun hits both the building and the surrounding ground, while heat also rises from the core of the earth. Heat energy from both the core and the sun become stored within the geneiss during the day. Because the geneiss is exposed to both the inside and outside surfaces, a thermal bridge is created, allowing the stored heat to be released inside the building. The outdoor pool is protected from the wind on 3 of the four sides and uses the thermal mass of water and stone to retain heat. The narrow slits, six centimetres, cut like a sharp knife the network overhead lights in the bathrooms, give structure to the upper partition, and also show visitors spa the next room extension, and therefore, support the structural concept of the architect, who always saw their bathrooms as a continuum, which is experienced as a whole, but do not see everything at once.(en.wikiarquitectura.com) These illumination joints are also the building’s expansion joints, which are required to allow for the expansion of various building parts due to temperature changes and horizontal and vertical movement. Illumination joints along the ceiling, water joints along the floor: some expansion joints along the floor accept water, but not all the floor joints conduct water, some are lined with bitumen, all ceiling joints, by contrast, are illumination joints. The intended idea and the achieved effect seek to define spaces with stone, water, and light. 2.0 Built using locally quarried Valser quartzite slabs, the building is made up of 15 different table-like units, 5 metres in height, with cantilevered concrete roof units supported by tie-beams. (www.dezeen.com) The composite load bearing baths consists of solid walls of concrete and thin slabs of Vals gneiss rock the place, broken or cut to size in the quarry just behind the village. The idea of Zumthor’s thermal baths was hollow giant blocks of stone, but the big blocks that could manufacture in Vals, transport and especially stacked to build walls using local labour, were small compared to the idea of height that wanted to give the space and the definition of the building. (Peter Zumthor Therme Vals – Sigrid Hauser Peter Zumthor). To achieve the desired effect monolithic one a “textile stone” was used, designing a model that allowed for the joints attaching the stones in a wall with homogeneous effect. The joint pattern finally developed in many work steps is based on the principle layering thin stone panels in three different heights: 31, 47 and 63 mm. These three-layer heights run through the whole bath from top to bottom. (en.wikiarquitectura.com)The entire structure extends to a width of approximately 58 meters and cuts as far as 34 meters into the slope in front of the main building of the hotel complex, a unit erected in the 1970s and which stands at the north-eastern corner of the property like a sweeping gesture with its four rows of loggias overlooking the grass-covered roof of the Therme. (www.arcspace.com)These units fit together like a giant puzzle. The nature of the construction is revealed through an inspection of the roof, the roofs of the units do not bind, and 8 cm holes are covered with glass to prevent water ingress. Fifteen rectangular stone blocks between 3 and 5 meters wide and 6-8 meters long support of the roof. They are distributed according to a strict grid of perpendicular lines and stand as monoliths arranged in a system of winches. The spa building consists of 15 units of different table, 5 meters high, with cantilevered concrete roof supported by beams. These fissures create a ‘dual impression’. On the one hand the roof looks very heavy but on the other, it appears to be floating in the air. (www.dezeen.com) (www.arcspace.com)Individual slabs are covered with grass in order to give the feeling of the continuation of the green mountain when being seen from the hotel’s balconies. Only the narrow glass lines that cover the fissures in order to protect the inside from the rain water can betray the existence of a building in this site. (www.worldarchitecture.org) The gaps between the slabs are of high importance for the atmosphere created in its interior. The natural light is creating a natural atmosphere while at the same time plays with the humid environment. It reflects in the steam and refracts in the water. Furthermore, the choice of the green roof enhances the main idea of the integration of the building with the natural environment. (en.wikiarquitectura.com)”… The flank of the valley opposite the thermal baths, an immense, sweeping slope with small barns to store hay; rectangular pastures, some mown, some for grazing, full of boulders, scored and inscribed with paths and fences. The meadow carpet is lumpy. It covers the stony flank of the mountain. …” Peter ZumthorIn total, 450 m³ of Vals quartzite panels were processed for the walls of the thermal baths, 3100 square feet of wall surface layers with 20 sqm. lengthall the strips together stone used is 62,000 linear feet.· Compressive strength: about 217 N/mm2· Density: 2,698 kg/m3· Crushed stone panels: thickness 63, 47 and 31 mm· Tolerance: 1 mm· Width: from 12 to 30 cm· Lengths: up to 3.20 m· Joint width: about 2 mmCores· Stone Bathtubs: polished cuboid, layered, stacked size between 0.5-1 m3· Sound Bath – Living Resonance: Stone heading inside· Sweat stone: polished and stained concrete· Stone Island: partition panels on a large scale up to 3 square meters per panel(en.wikiarquitectura.com) There are 60,000, 1-metre-long sections of stone forming the cladding of the walls. Whilst these initially appear random, like an ashlar wall, there is a regular order. The cladding stones are of three different heights, but the total of the three is always 15cm, so it allows for variety in arrangement, whilst facilitating construction. (Peter Zumthor Therme Vals – Sigrid HauserPeter Zumthor) 3.0 The layered construction of the walls as well as the expansive network of technical infrastructure required for the provision of comfortable conditions for the programme are in direct contrast with what is expressed in the areas experienced by bathers, which are characterised by a minimal, seemingly simple and unassuming aesthetic. Moreover, what is apparent in Therme Vals is a recurring motif of concealment in which the architect very purposefully employs the use of systems which are subsequently hidden from the view of the bathers. (Peter Zumthor Therme Vals – Sigrid Hauser, Peter Zumthor)This aspect of the scheme’s role in the construction is best illustrated in a series of key moments, most notably in the assembly of the external walls of the building, the relationship between the inner concrete cores and its accompanying layers and the fitting of the thermally insulated window frames. (www.arcspace.com) In keeping with the technique of perimeter insulation outlined previously, a thin layer of insulation is applied on the exterior perimeter of the building which cuts the concrete floors slabs into two pieces which rest on the same pillar. This layer extends upwards and meets the horizontal insulation layer of the roof slab, thus providing a continuous insulating perimeter. The same technique is used in the side fittings of the window frames which are held in place by T-shaped insulation members adjoined to the primary insulating layer. The windows are subsequently placed directly onto these thermally insulating fittings preventing any loss through the contact of the window frames with the cold exterior concrete and stone compound masonry. (Peter Zumthor Therme Vals – Sigrid Hauser, Peter Zumthor) The effect of the compound masonry surface however is never disrupted by the underlying complexity; on the contrary it binds it and conceals it, thus maintaining the continuous appearance of the stone layers. 4.0 Also, subject to this motif of concealment is the treatment of the building’s heating system. Making use of a concealed system of hypocausts, the under-floor heating system permeates the entirety of the building’s interior, however its existence is only visible in the form of air vents in front of the double height thermally insulated windows. (Peter Zumthor Therme Vals – Sigrid Hauser, Peter Zumthor) The underlying network of tubing and pipes is places underneath the floor-slabs of stone of the primary circulation spaces, and thus meanders and branches off into various directions accordingly. In a similar fashion to the underfloor heating system, the channelling of overflowing water is also concealed beneath the floor. This integration is best seen in the water over-flows constructed at the end of the steps of each pool. (en.wikiarquitectura.com) The over-flows of all the pools are subsequently interconnected and form a discrete network of water channels which is only revealed through the presence of fissures along the floor designed to remove any excess water. This network of water channels ultimately concentrates waste water in the water treatment gullies underneath the indoor and outdoor pools.