Therme Vals Case Study: Stone, Light and Plan (Peter Zumthor)

Therme Vals is a thermal bath in the Swiss Alps, designed by Peter Zumthor and opened in 1996, built from tens of thousands of thin slabs of local stone and half sunk into a hillside. For a case study, three ideas carry almost everything: walls laid up in thin courses of Vals stone, daylight let in through narrow slots between roof slabs, and a plan made of solid blocks where the bathing happens in the spaces between them.

The sections below follow the order a studio jury expects. For the full method, see our guide on how to document a building for an architecture case study.

The brief and the client

Vals has used its hot spring for bathing since the 19th century. A hotel complex was built next to it after the war: Domus dates it to 1960, while Metalocus gives 1970. By the 1980s the complex had lost its appeal, and the village decided to build a new bath. According to Architectuul, the community bought the bankrupt hotel in the early 1980s and then commissioned Zumthor.

The Domus review of 1997 notes that the council chose Zumthor's proposal knowing it would be difficult and expensive to build. The client was a mountain village of about 1,000 people (Swissinfo, 2004), betting a public asset on architecture.

Site and context: Therme Vals location

Vals sits at the end of a deep valley in Graubünden, about 1,200 m up, according to Domus 798 (November 1997, republished 2023). The thermal springs here are the only ones in the canton.

The new bath does not attach itself to the hotel. Domus describes it as standing alone and half sunk into the earth, linked to the hotel only by an underground passage. Its roof is planted with grass, so from above it reads as part of the slope. Zumthor's own explanation, quoted in Domus, was that the building gives up fitting in with the existing buildings in order to "bite more deeply" into the mountain and its geology.

Therme Vals concept: mountain, stone and water

The concept is usually summed up in Zumthor's own phrase, "Mountain, stone, water" (quoted by Thisispaper and others), followed by a list of ways of building in, with and out of stone. The wording varies between sources, so check it against Zumthor's own published texts before you put it on a sheet. The intention, quoted in Domus, was a building that feels older than its neighbours. Domus quotes the description of the whole building as "a great porous stone".

Two further ideas follow from that:

• Bathing as a slow sequence of experiences. Domus lists the rooms by the names Zumthor gave them: a sweating stone, a showering stone, a massage block, a drinking stone, a relaxation room, a fire bath, a blossom bath, a cold bath and a sound stone. The names describe what you feel, not the equipment.
• Time set aside. According to Architectuul, Zumthor first wanted no clocks in the bath at all. Three months after opening, two small clocks on brass posts were added.

Therme Vals plan: solid blocks and the space between

The plan is the most useful thing to study. Metalocus describes 15 volumes set on a strict grid, each about 5 m high, 3 to 5 m wide and 6 to 8 m long. Each of these blocks is solid on the outside and hollow inside: the small, specific rooms (the fire bath, the cold bath, the drinking stone, the showering stone) sit inside the blocks. The large indoor pool and the circulation are not rooms at all. They are the space left over between the blocks.

Three things follow for a plan analysis:

1. Zoning by mass, not by walls. The solids hold the intimate uses and the voids hold the shared ones: a field of stones with water around them.
2. Circulation without a set route. Domus calls the layout labyrinthine. There is no single path, and the gaps open and close views as you move.
3. The hillside and the valley sides behave differently. The building backs into the slope; towards the valley, deep cuts in the stone frame the view.

Our diagram shows the principle only. The real plan is published in the book Peter Zumthor Therme Vals (Scheidegger & Spiess, 2007), which includes Zumthor's sketches and plans with photographs by Hélène Binet. Use it for any measured redrawing, and credit it. ArchDaily's project page has photographs and credits.

Therme Vals section and structure: the "tables"

In section, each block works like a table: the stone-clad block is the leg, carrying its own cantilevered concrete roof slab. Domus describes these as large "tables" with widely projecting ceilings, set slightly apart from each other in a geometric pattern. Architectuul adds that the roof units are held by tie-beams and fit together like a jigsaw, and that they never touch: the gaps between them are about 8 cm wide and covered with glass to keep the water out.

Structurally, Metalocus describes the load-bearing system as solid concrete walls working with thin slabs of Vals stone, which Domus calls "Vals laminated stonework" (Valser Verbundmauerwerk): stone and concrete built up together as one mass, not stone tiles hung on a finished frame. Metalocus also reports that Zumthor first wanted to hollow the rooms out of giant stone blocks, and turned to thin layers when that proved technically impractical.

Therme Vals materials: Vals stone, laid in thin courses

The stone came from a local quarry. Swissinfo (2004) names the Truffer family quarry and quotes Pius Truffer on the stone's varied colours and its resistance to frost, which lets it work inside and outside. ArchDaily lists Truffer as a supplier.

On quantity and coursing, the sources do not fully agree, and a careful case study should say so:

• Number of slabs: the operator, 7132, says 60,000 slabs. Swissinfo's 2004 article says about 40,000 stone tiles.
• Course heights: Metalocus gives three heights of 31, 47 and 63 mm. Architectuul says the three heights always add up to 15 cm. The three Metalocus figures add up to 141 mm, so the 15 cm figure presumably includes the joints; we have not seen a drawing that settles it.
• Length: Architectuul says each piece is about 1 m long.
• Name of the stone: the operator calls it Vals quartzite; Metalocus calls it Vals gneiss and notes it is also known as Valser Quarzit.

What is not in dispute is the method. Domus reports that Zumthor drew and dimensioned the individual cladding stones and specified which stone went where. The same lamination runs through walls, pool floors, steps, benches and door openings. The Pritzker Prize 2009 laureate page points out how the horizontal joints of the stone echo the horizontal line of the water, set against warm bronze railings.

Therme Vals lighting, water and climate

Daylight. Much of the daylight inside arrives from above, through the glazed slots between the roof slabs; Domus describes slits that let the light in from above. The Pritzker page describes the effect as a line of light that emphasises the movement of the water. On the valley side, the deep openings give framed views out.

Water. The operator says the water comes from the St. Peter spring at about 30°C. Older sources give different figures: Domus (1997) says the spring water emerges at 26°C, and Swissinfo (2004) reports two springs at 25°C and 29.8°C, with about half the flow going to the Valser mineral water bottling plant. We found no official list of individual pool temperatures, so we do not quote one.

Climate and mass. Half buried and built of heavy stone and concrete, the building holds a steady temperature; Metalocus reports that the volumes are heated using their thermal mass. We found no detailed published account of the mechanical services.

Reception: praise, problems and a change of owner

Domus reviewed the bath in November 1997, a year after it opened, calling it "already a monument of European architectural history" and noting it had also proved a commercial success for tourism. The same review was not uncritical. It argued that the poetic names Zumthor gave the rooms tipped the bath towards a "New Age" reading, and that even a strict architectural idea could be bent by consumerism once it was marketed.

Official recognition came quickly. The government of Graubünden placed the bath under heritage protection in 1998, less than two years after opening (SRF, 2020). When Zumthor won the Pritzker Prize in 2009, the jury cited "the mineral mist in the thermal baths at Vals" as an example of his attention to the senses.

In March 2012 the village voted to sell the bath and hotel to the property developer Remo Stoffel for CHF 7.8 million. Swissinfo reported a vote of 287 for Stoffel's offer against 219 for a rival bid by Zumthor, and that the village could not afford the investment the hotel needed (Swissinfo, 2012). The complex was renamed 7132.

• In 2015, Dezeen reported a proposal by Morphosis for a 381 m hotel tower beside the bath, then planned for 2019 (Dezeen, 2015). We found no report that it has been built.
• In 2017, Dezeen quoted Zumthor as saying the bath's original social idea had been lost, saying "this social project is dead", while noting that the listed bath itself was protected (Dezeen, 2017).
• A criminal complaint over the sale, filed by the cantonal government in 2017, was closed in 2020. The investigation found the company's board had not harmed it, and an expert opinion found the price was above the company's intrinsic value and appropriate (SRF, 2020).

What designers in India can take from Therme Vals

These are our reading of the building, not claims made by its architect.

1. Use the stone your region already quarries, and design the coursing as a system. Vals turned a local stone into a family of three course heights. Indian practice has the same opportunity with Kota, Shahabad, Tandur or Dholpur stone, which are already sold in thin slabs. Fix a small set of course heights and lengths, draw the bands, and let masons mix within them. Our guide to natural stone for houses compares the common Indian options.
2. Plan with solids and voids. Putting toilets, stores, stairs and wet areas inside thick "blocks" and leaving the shared space as what is left between them works at the scale of a house as well as a spa. The blocks also hide ducts and pipes. For a thesis, wellness centres and community baths are a strong typology to test this; see our list of B.Arch thesis topics by typology.
3. Top light through narrow slots suits hot climates, if the slot is detailed for rain. A thin slot brings daylight deep into a plan with far less heat gain than a large window or skylight. Vals glazed its 8 cm gaps to keep water out. In an Indian monsoon, that slot needs upstands, falls and a reachable gutter; our guide to waterproofing by climate covers the basics.
4. Sink the building and plant the roof where the site slopes. On a hill site in the Western Ghats or the Himalaya, cutting into the slope and planting the roof reduces the visible mass and steadies indoor temperatures. Design the drainage and retaining walls first.

Visiting Therme Vals

The bath is run by 7132, which also runs the neighbouring hotel. According to the 7132 day-visitor page, checked on 3 Nov 2026:

• Day visitors need an online reservation. Tickets are limited and can be cancelled online up to 24 hours before.
• Opening hours for day visitors are 11 am to 6 pm on Monday and Tuesday, and 11 am to 8 pm from Wednesday to Sunday.
• The page lists adult tickets at CHF 70 on Monday and Tuesday and CHF 85 from Wednesday to Sunday. Check the page before you go, as prices change.
• Children from 6 years are allowed with adults. There is no time limit, but no re-entry.
• Phones, tablets and other devices with cameras are not allowed in the bath.

For students, that last rule means sketching from memory afterwards and using published photographs, such as Hélène Binet's in the 2007 book, for your sheets. The exterior and roof can be seen from the surrounding slopes.

Looking for someone to design with this kind of care for material and light? Find an architect on MOA.

FAQ

When was Therme Vals built?

It was built from 1993 to 1996 and opened in 1996. The village had bought the old hotel complex in the early 1980s and then commissioned Peter Zumthor. It was given heritage protection by the canton of Graubünden in 1998.

Who is the architect of Therme Vals?

Peter Zumthor, the Swiss architect based in Haldenstein, who won the Pritzker Prize in 2009. ArchDaily credits Marc Loeliger, Thomas Durisch and Rainer Weitschies on the team.

What materials is Therme Vals made of?

Local Vals stone, laid in thin horizontal courses together with load-bearing concrete, with concrete roof slabs, a planted roof, glass in the roof slots and bronze or brass for railings and fittings. The operator says 60,000 stone slabs were used; one older report says about 40,000.

Where is Therme Vals located?

In the village of Vals, at the end of a valley in the canton of Graubünden in eastern Switzerland, about 1,200 m above sea level. The complex's current name, 7132, is also the village's postcode.

Where can I find Therme Vals plans and sections?

The most complete source is the book Peter Zumthor Therme Vals (Scheidegger & Spiess, 2007), which includes Zumthor's sketches and plans. ArchDaily's project page also shows drawings. MOA's diagrams in this post are schematic and not to scale.

Sources

• 7132: 7132 Thermal Baths, Peter Zumthor (accessed 3 Nov 2026)
• 7132: 7132 Thermal Baths: day trip, general information and prices (accessed 3 Nov 2026)
• Domus: Peter Zumthor's thermal baths in Vals (Domus 798, November 1997, republished 2023) (accessed 3 Nov 2026)
• The Pritzker Architecture Prize: Peter Zumthor, 2009 Laureate (accessed 3 Nov 2026)
• ArchDaily: The Therme Vals / Peter Zumthor (accessed 3 Nov 2026)
• Metalocus: A place to leave time in suspension. The Thermal Baths in Vals by Peter Zumthor (2018) (accessed 3 Nov 2026)
• Architectuul: Thermal Baths Vals (accessed 3 Nov 2026)
• Swissinfo: Stone and water temple delights the senses, Dale Bechtel (2004) (accessed 3 Nov 2026)
• Swissinfo: Vals thermal baths change hands (2012) (accessed 3 Nov 2026)
• SRF: Kein Prozess: Verfahren zum Verkauf der Therme Vals eingestellt (2020) (accessed 3 Nov 2026)
• Dezeen: Morphosis unveils plans for "minimalist" skyscraper next to Zumthor's Therme Vals, Anna Winston (2015) (accessed 3 Nov 2026)
• Dezeen: Therme Vals spa has been destroyed says Peter Zumthor, Jessica Mairs (2017) (accessed 3 Nov 2026)
• Thisispaper: Thermal Baths in Vals by Peter Zumthor, Alexander Zaxarov (2020) (accessed 3 Nov 2026)
• University of Chicago Press (for Scheidegger & Spiess): Peter Zumthor Therme Vals (2007) (accessed 3 Nov 2026)