Erden.at , Martin Rauch

 

Martin Rauch, founder and managing director of Lehm Ton Erde (LTE) in Schlins, Austria, is internationally known as a leading expert in the field of rammed earth mining. He founded the company in 1984 as the sole manufacturer of ceramics and clay construction, and then founded Lehm Ton Erde Baukunst in 1999. The current studio and operations centre were built in 1990, where he presented his accumulated knowledge of clay construction at the time. Over the course of more than 35 years of working with clay, Rauch and LTE have completed over 100 projects around the world, published 3 books and led the industry in rammed earth innovations.

 

After the development of a unique precast plant, Lehm Ton Erde is now entering a new phase in which it is a matter of establishing rammed earth as a sustainable building material in order to counter the ecological burdens of the construction industry. ERDEN means clay. It is a grounding of building in natural materials and processes. Clay earth continues to be the roof for everything that has to do with rammed earth. ERDEN is a leader in clay construction prefabrication and is revolutionizing the construction industry. With the ERDEN factory hall, a new plant and headquarters for the production of precast clay elements. The team is made up of people from diverse backgrounds, including design, craft, teaching, research, and management expertise.

 

The ecological résumé of rammed earth is second to none. No other material has a smaller footprint on our planet. The raw material and the finished product are one and the same. Soil from the ground is dug up and processed. We add a little gravel or clay to optimize them, mix them with water and voilà!

 

This diagram emphasizes the cyclical nature of rammed earth construction, which starts and ends with the natural earth, with minimal environmental impact. This aligns with Martin Rauch’s philosophy of sustainable building, where the material’s life cycle, from construction to deconstruction, supports ecological balance​.

1- Earth Site: Earth is extracted directly from the building site or a nearby location, using local resources to minimize environmental impact. This is where the raw material for the rammed earth process begins.

2- 100% Earth: The material used for construction is pure earth, without additives. The earth is gathered and sometimes modified by adding gravel or sand, depending on its natural composition.

3-Filling the Formwork: The extracted earth is placed into formwork, which is essentially a mold that shapes the walls. The formwork holds the earth in layers before it is compacted.

4-Compacting Earth: Once the earth is inside the formwork, it is compacted. This can be done manually or with the help of mechanical tools such as pneumatic hammers. The compaction process is crucial for the stability and durability of the walls.

5-ConstructionThe walls are constructed by repeating the process of filling and compacting. The compacted earth forms solid, load-bearing walls without the need for additional finishing materials like stucco or plaster.

6-Seamless Finishing: After the compaction and construction of the walls, seamless finishing techniques are applied. This helps to smooth out the surface and enhances the natural aesthetics of the rammed earth, maintaining the integrity and beauty of the material.

7-Transport: If needed, components of the rammed earth can be prefabricated and transported to the site. Prefabricated elements simplify the construction process, especially for large or complex structures.

8-Building in UseThe rammed earth structure is then ready for use. These buildings have high thermal mass, providing excellent insulation properties, which make them energy efficient and comfortable to live in, regulating temperature naturally.

9-Deconstruction: At the end of the building’s life cycle, it can be deconstructed. The natural earth material can be reused or returned to the site, making it a completely recyclable and sustainable material.

10-Earth Back to Site: Once the building is deconstructed, the earth is returned to the site, completing the cycle. This step emphasizes the eco-friendly nature of the process, where no waste is generated, and the material is fully reused.

 

Despite its ecological, functional and aesthetic qualities, rammed earth has hardly been used in recent times. Especially because the experience with the material has been lost. For us, every rammed earth building was, if you will, a prototype. The costs were correspondingly high. Thanks to Martin Rauch’s 35 years of work, rammed earth is now losing this exclusivity. With the introduction of the ERDEN prefabrication process, we have simplified clay construction and made it more affordable. This means that the desire to build their own mud house is becoming a reality for more and more people. But there is still a long way to go. Regulatory hurdles and a broader knowledge of working with rammed earth still pose challenges. But the upswing has begun. The environment urgently needs natural building solutions. Why doesn’t everyone build with clay? Well, it’s only a matter of time.

 

An urban-rural furniture
There’s nothing new about Earth’s resources becoming scarce, just as public space, especially in urban areas, is becoming increasingly scarce. Only what is the solution? The construction industry is one of the major polluters of our time. The Erdenbürgerin project is something of a prototype for a counter-reaction. A seating place made of 100% earth, the most sustainable building material in the World. The earth used to build this urban-rural furniture comes from our local surroundings.

Of course, this is not the silver bullet either. Rather, it is an impetus and an opportunity to ask questions. Where am I sitting here? And on what? The Erdenbürgerin asks you to take a seat and to widen your gaze. Or just to sit and commune, to chat, to relax. In a freespace, public place, as a healthy society needs. And a healthy environment. This project was developed as a cooperation between the Walgau region and earth specialists, Lehm Ton Erde.

 

Schlins, the Mecca of rammed earth architecture, one could say, is the home of the founder of ERDEN, Martin Rauch. Since he opened his office in Schlins, several works have been created in the small town in the Vorarlberg province that have become important international precedents of contemporary rammed earth architecture. These include the Rauch Workshop, Haus Rauch, our ERDEN workshop and the Erdenhaus, which is still under construction.

 

Rauch family home

Schlins: Austria

Project by Martin Rauch (Lehm Ton Erde GmbH, Schlins, AT) and Roger Boltshauser.

The materiality and form of the residential house are direct reactions to the steep south-sloping scarp situation of the slender plot in its landscape context – as if a monolithic block, similar to a piece of abstract and artificial nature, had been pressed out of the earth. Two clefts articulate the building of rammed earth, wedging it backwards with the scarp and establishing a frontal prelude or welcoming gesture towards the valley. The inside of the house is developed in the form of sequences of individualizable spaces that respond storey-wise to the variable conditions. As opposed to more organic, archaic clay architecture, the morphology of the building aims towards a certain clarity and sharp-edgedness. The strips of clay bricks that are inserted between the typical clay layers optically stabilise the building structure by emphasising the horizontality and heightening the light and shadow effects.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

References 

1- https://www.architectsnotarchitecture.com/archive/martin-rauch/

2- https://www.erden.at/

3- Rammed earth house, Rauch family home by Boltshauser Architekten | Detached houses (architonic.com)

 

 

Gramazio and Kohler: Remote Material Deposition

Gramazio and Kohler is a research group based in ETH Zurich, Switzerland, who consider the “interlinking of data and material and the resulting implications for architectural design” [gramaziokohler.arch.ethz.ch]. Working between material, manufacturing logic, and the design process, the group uses technology, robots, and programming as a means to define a new architectural expression.

Remote Material Deposition Sitterwerk Timelapse

Interrogating methods and workspace limitations of the construction/build process, Remote Material Deposition literally builds from afar; “remote material”, as in material situated at a distance, and “deposition” as the ejection, depositing, and/or build up of a material.

Ballistic trajectories of light projectiles through bulb exposure

A robotic catapulting device, which is hooked up to a camera sensor installed at a birds-eye view, is installed within in a confined workspace. The catapulting device is loaded with loam projectiles, a composite soil made of clay, sand, and silt. The material in this process must be able to adhere to its fellow material upon impact, and harden after. For this reason loam (mud, earth) was chosen as the primary building material. The loam is shaped in cylinders, as to maximize the colliding forces of impact in order to adhere to the existing materials that were “shot” before it. Below is a diagram of the workspace.

Since uncertainties are bound to occur with the depositing, or lack of depositing, of the loam projectiles the over head sensor captures the mistakes, uncertainty, and data from the build, sends that information back to the design system (computer), and adjusts for the next round of projectiles. Although a defined proposal for design is used to set up and initialize the machine, the construction and build process becomes the design process; the two are linked in a feedback loop.

Design + Feedback loop

The use of earth/loam in this context is necessary for the method of construction applied, the adherence of projectiles, however the material and concept of this application can exist independently. What would the process of “ballistic architecture” look like at a much larger scale, if material were not a condition?

Consider the word “ballistics”: missiles, bombs, destruction. Countries such as Palestine and Afghanistan  (and so many more) have had entire historical and cultural identities destroyed through ballistic warfare and destruction of their architecture and built infrastructure. It is an incredible thought to place Gramazio and Kohler’s work in the context of ballistic creation. Instead of destroying each other through missiles and projectiles, can countries and nations build each other instead?

Size: 12 m × 12 m and a ceiling height of 7 m (interior construction space)

Year: 2014

Photos: ETH Zurich, Gramazio and Kohler, Michael Lyrenmann

Architects: Gramazio and Kohler

Students: unknown

References:

[1] https://gramaziokohler.arch.ethz.ch/web/e/lehre/277.html Gramazio Kohler website

[2] https://www.researchgate.net/publication/317340911_REMOTE_MATERIAL_DEPOSITION Conference Paper

[3] https://vimeo.com/100784860 Production video

Traditional Ukrainian Building Techniques: Mazanka

For centuries, Ukrainians have utilized the earth to create diverse and resilient dwellings. While wood played a role in certain regions, earthen construction techniques were widespread, particularly in the steppe and forest-steppe zones where wood was scarce. One of the most common methods was wattle and daub, employed as far back as the Neolithic Trypillian culture (5500-2750 BC). This involved creating a woven lattice of wood (“wattle”) and then applying a mud or clay mixture (“daub”) to form the walls. This technique, while simple, provided sturdy and well-insulated structures.  While the actual structures haven’t survived, the archaeological evidence provides insights into their building techniques. Museums like the Museum of Folk Architecture and Way of Life of Central Dnieper Ukraine in Pereiaslav preserve examples of traditional building techniques, including earthen structures. The museum is part of Pereiaslav National Historical and Ethnographic Reserve. It was created in the 1960s and is the first open-air museum in Ukraine. The skansen (open-air) area on the picturesque Tatar Mount is divided into several sections: a pre-Soviet Ukrainian village of the Middle Cis-Dnipro Region, crafts and trades of a reformed Ukrainian village, windmills, and the earliest period section. Its total area of 25 hectares contains about 300 items, 122 of which are folk architecture monuments from the 17th to 19th centuries. They include 20 households with dwelling houses and outbuildings, presenting over 20,000 artifacts, such as works of folk craftsmen, lobar tools, household items, archaeological materials, documents, and photos.

Links:

Neolithic Trypillian cultureMuseums like the Museum of Folk Architecture and Way of Life of Central Dnieper Ukraine in Pereiaslav, Pyana Hata restaurant, Ukrainian hata Wiki, Ukrainian hata, Mazanka, Museum of Folk Architecture and Folkways of Ukraine

Neolithic Trypillan settlements, Southeastern Europe1914

Ukrainian traditional houses were generally built facing south to maximize sunlight for warmth. This often resulted in houses being positioned at various angles to the street, especially in hilly areas with complex terrain, creating a charmingly haphazard village layout. In flatter regions, houses were more likely to be aligned with the street.

19th century

1929

In rural areas, the tradition of earthen construction continued to flourish, shaping vernacular architecture. Homes, outbuildings, and even churches featured cob walls made from a mix of clay, sand, and straw. This readily available material created thick, insulating walls that were well-suited to the Ukrainian climate.

Another prominent technique was the construction of mazanka houses. This type of house got the name mazanka from the word mazaty  (Ukrainian: мазати; to smear, to grease, to plaster with clay mortar). These structures usually utilized a wooden frame filled with clay mixed with straw or reeds, brushwood, or woven willow branches. The walls were then plastered with a clay mixture and whitewashed, creating a distinctive and practical dwelling.  The choice of technique often depended on the availability of local materials. They dominated areas with limited wood, clay, and straw, while regions with more forests might incorporate more timber framing. This adaptability is a hallmark of Ukrainian earthen building traditions, reflecting a harmonious/sustainable relationship between builders and their environment.

 

 

 

 

 

 

 

 

 

 

 

 

Ukrainian San Antonio Українське Сан Антоніо Homestead Батьківська ХатаFrom left to right: 1st room is a house (with a clay oven), inner porch (siny), and outbuilding (food storage, household items, or even an animal stall).

 

 

 

 

The architectural appearance of the folk dwelling – “khata” – and its internal organization in its main features are common throughout Ukraine.  Khata is a rectangular, somewhat elongated building in plan, covered with a hipped roof; the ratio of the width of the building to the length ranges from 1:1.25 to 1:2.25.

The living space itself approaches a square – the most economical rectangular shape of a room, in which the perimeter of the walls and the cooling of the room are the smallest. A large entrance hall and a pantry attached to the living space lengthen the plan. If the hut is built for two independent living spaces with an entrance hall between them, then the building is stretched along the main facade and acquires an elongated shape.

 

 

 

 

 

The most typical roof design in Ukraine was a hipped roof with four sides and sloping ends supported by rafters. These rafters were either attached to the top of the log walls or to longitudinal beams laid on top of the walls. In the Polissya region, a gable roof (two-sided) was also common, constructed in a few different ways: with a log covering, using supports shaped like chairs, or with posts supporting a main beam and the entire roof.

Roofs were typically covered with straw, either bound in sheaves or spread loosely. In forested and mountainous areas, the log structure of the house was left exposed, showcasing the craftsmanship of the interlocking logs. In the steppe and forest-steppe zones, houses were usually whitewashed inside and out, regardless of the building material, creating a striking contrast against the surrounding greenery. Colorful accents around windows, doors, and the base added a cheerful touch.

 

 

 

The simplest Ukrainian hut had two rooms: a large entrance hall used for storage and a warm living area. The stove dominated the living space, serving as a cooking area, storage space, drying rack, and even a bed! Kitchenware was kept near the entrance, while the sleeping area was located at the back, away from the windows.

 

 

 

 

The floor was made of earth in the early periods and later also had a special clay base. Only in some regions of Ukraine was the floor made of wood.

 

These time-tested techniques, passed down through generations, not only provided shelter but also shaped the unique character of Ukrainian villages. The whitewashed walls of mazanka houses, nestled among gardens and fields, created a picturesque landscape that continues to define the rural Ukrainian identity. Though modern materials have become more prevalent, the legacy of earthen construction remains an important part of Ukraine’s architectural heritage.

Here, you can check out a contemporary documentary film about the vernacular architecture of Ukraine filmed during the war, where multimedia platform Ukraïner and film studio Craft Story have teamed up for a special five-part documentary series entitled ‘STRIKHA’ (meaning ‘the roof’ in Ukrainian). Based on a long-term expedition throughout all regions of war-torn Ukraine (except those occupied by Russia), the series portrays the country’s authentic and vernacular architectural ‘treasures,’ particularly those hidden in distant villages, away from the main road.

Here’s an example of a contemporary take on Ukrainian earthen building utilizing the wattle, daub, and cobb techniques. The Ukrainian architecture firm of architect Yuriy Ryntovt built the restaurant Pyana Hata in Kharkiv in 1999 (literal translation: “drunk house,” but now you know that khata/hata means not just a house but an earthen plus wooden structure) that may playfully resemble an ancient Neolithic Trypillian culture aesthetics.  The building area is 350 m2, and the site area is 0.4 hectares.  

Yuriy Ryntovt is born in 1966. Head of the creative workshop Ryntovt Design (Kharkov), specializing in architectural design, furniture, and interior design. Co-founder and artistic director of the theater and concert club “RODDom.” 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

IAAC: Open Thesis Fabrication

image of 3d printing robot making curvy cellular forms out of clay
Image Source: OTF Booklet

Open Thesis Fabrication is a six-month applied research program for postgraduates at the Institute for advanced architecture of Catalonia.

The program focus is on combining additive manufacturing with construction technology to create sustainable architecture with key areas of research in robotic manufacturing, material research, and performance-based design.

The program works with non-governmental organizations to develop designs for use in African humanitarian contexts and is comprised of architects, engineers, designers, and professionals with previous knowledge of digital fabrication and computational design.

It’s learning objectives are for program participants to:

  • Gain experience in large-scale 3D printing
  • Develop skills in digital fabrication, computational design, and material research
  • Learn to provide architectural solutions considering various aspects of construction

This is achieved through the implementation of three phases, Exploration, Prototype Design Charettes, and Prototype Construction.

chart that displays the phases of implementation and timeline
Image Source: OTF Booklet

Examples of projects that have been completed include:

  • Digital Adobe – A 2-meter wide and 5-meter-high printed clay wall [2017-2018]
  • Terraperforma – A façade design of parametrically constructed modules optimized for solar radiation, wind behavior, and structural 3D printing [2016-2017]
  • Digital Urban Orchard – A wooden pavilion made with digital and robotic fabrication divided into a wooden structure, aquaponic system, and silicon skin designed to capture the ideal solar radiation for winter and summer.
  • Minibuilders – a family of small-scale construction robots that are capable of constructing objects larger than itself in order to address the limitation found in additive manufacturing that often constrains the proportions of fabricated objects to the size of the machine.
Image Source: OTF Booklet
Image Source: OTF Booklet
Image Source: OTF Booklet

 

Image Source: OTF Booklet
schematic and images of mini robots being used to produce clay structures larger than the size of the machine
Image Source: OTF Booklet

For more information regarding tuition fees, how to apply, grading systems, etc., be sure to check out IAAC OTF resource guide: https://iaac.net/wp-content/uploads/2019/07/OTF_Booklet_2019-22-07-2.pdf

 

 

Impact Printing: Gramazio Kohler Research

Location:  ETH Zurich
Year:  2021-2024
​Research: Gramazio Kohler Research

 

 

Source: https://gramaziokohler.arch.ethz.ch/web/e/forschung/451.html

Impact printing is an innovative robotic construction method that creates full-scale, freeform structures using a custom earth-based material. Unlike traditional layer-based 3D printing, it employs high-velocity deposition, allowing for interlayer bonding at speeds of up to 10 meters per second. The environmentally friendly material consists mainly of locally sourced secondary materials with minimal mineral admixtures.

Currently, prototypes are being developed at ETH Zurich’s Robotic Fabrication Laboratory, with plans to integrate this technology into the HEAP autonomous excavator. The research also focuses on developing a digital design and construction strategy, utilizing advanced computational design and sensing methods. This work aims to enhance sustainable, mobile robotic construction, leading to groundbreaking techniques in the design and manufacturing of earthen structures.

Video

 

Source: https://www.research-collection.ethz.ch/handle/20.500.11850/668921

The diagram displays different concepts of earth material fabrication methods.

Left: ‘throwing’ technique used during Remote Material Deposition in 2014, Middle:‘pressing’ technique used during Clay Rotunda in 2021,  Right: ‘shooting’ technique currently investigated during Impact Printed Structures.

Source: https://www.research-collection.ethz.ch/handle/20.500.11850/668921

The diagram above illustrates the ideal overlap between each deposited component.

Source: https://www.research-collection.ethz.ch/handle/20.500.11850/668921

The photo above shows the process of printing a wall with a window embedded.

Déchelette Architecture: Quatre Cheminées

 

The project located in Boulogne-Billancourt in the Parisian suburbs, involves a building with eight social housing units, a caretaker’s lodge, and a shop on the ground floor, with a raw earth facade on the street side, a stone base and a wooden facade on the garden side. It is driven by a desire for restraint in design and the use of natural, bio-sourced, and local materials without ever losing sight of comfort for the occupants.

 

 

The building rises on five levels including a ground floor, four floors of housing and a green roof. It is structured around a central circulation core including an elevator and a staircase serving all levels. The search for optimization, transversality and independence of spaces guided our design.

The façade at street level is made of raw earth blocks, thus following the precepts of the “cradle to cradle” concept based on two principles: zero pollution and 100% reusability. The rammed earth used in the project comes from local sources, specifically from the excavation of the Greater Paris metro. This reduces carbon emissions from transportation and follows the circular economy principle.

 

 

 

Rammed earth bricks are prefabricated , differing from the traditional on-site method. This technique speeds up construction and ensures consistency and quality control, and  offers flexible installation in complex urban settings. Rammed earth bricks are placed on a stone base ensures both structural integrity and environmental sustainability.

Location: Boulogne-Billancourt, France

Completion: 2023

Project Area: 350 m2

Budget: €1,700,000 excluding VAT

Architect(s): Déchelette Architecture

REFERENCES

https://www.dechelette-architecture.com/quatre-cheminees/

https://europe40under40.com/project/17-rue-des-4-cheminees-2023-emmanuelle-dechelette-boulogne-billancourt-france/

https://www.boulognebillancourt.com/information-transversale/actualites/le-plus-haut-batiment-en-beton-de-chanvre-a-ete-construit-rue-de-bellevue-2996

https://www.facebook.com/dechelettearchitecture/?locale=ms_MY

 

Nandi House, Fino Lozano/Moro Taller de Arquitectura

Nandi House / Fino Lozano + Moro Taller de Arquitectura - Image 1 of 25
Photograph by Rafael Palacios Macias

Located in the town of San Jose de Garcia in Michoacan, Mexico, Casa Nandi is a collaborative project between architect Fino Lozano and the firm Moro Taller de Arquitectura. This two-story residence is designed to blend with its natural environment while offering views of the landscape. The home employs rammed-earth construction techniques combined with concrete elements such as casting, creating a balance between traditional and modern building methods. The design aims to respect the local context while providing a functional and aesthetic living space.

Architects: Fino Lozano, Moro Taller de Arquitectura

Area: 1345 ft²

Year Built: 2022

City/State: San Jose De Garcia, Michoacan

Country: Mexico

By making the most of its orientation to create a bright, intimate space, the residence also emphasizes the simplicity of its surroundings. Its natural ventilation which is derived from its forms, creates moments of release within the home that allow for contemplation of not just the environment but of self-embracing elements of harmony and tranquility for the inhabitants.

Nandi House / Fino Lozano + Moro Taller de Arquitectura - Image 20 of 25
Ground Floor Plan Courtesy of Fino Lozano and Moro Taller de Arquitectura
Nandi House / Fino Lozano + Moro Taller de Arquitectura - Image 23 of 25
Section Render Courtesy of Fino Lozano and Moro Taller de Arquitectura

Constructed upon pine wood beams, the building also features handcrafted mud bricks supporting a concrete slab that indeed displays the underlying natural elements for an effortlessly elegant yet raw appearance. As previously indicated, the walls that make up the house are a combination of modern concrete techniques and traditional rammed earth, providing a juxtaposition that emphasizes how timeless architectural building practices can be. This combination offers acoustic and thermal insulation in addition to structural support.

Nandi House / Fino Lozano + Moro Taller de Arquitectura - Image 17 of 25
Photograph by Rafael Palacios Macias
Nandi House / Fino Lozano + Moro Taller de Arquitectura - Exterior Photography
Photograph by Rafael Palacios Macias

Every material used in the home is on display, allowing each texture and color to contribute to a visual experience that authentically reflects the surrounding landscape. Rammed earth construction is popular in conveying the essence of Mexican architecture and Casa Nandi is a great example due to its rosy pink walls of local mud, creating a seamless connection between the home and its environment. “Casa Nandi, in that spirit, stands out yet settles in the place it belongs to” (Zohra Kahn).

Nandi House / Fino Lozano + Moro Taller de Arquitectura - Interior Photography, Kitchen, Beam, Facade
Photograph by Rafael Palacios Macias

References:

Caballero, Pilar. “Nandi House / Fino Lozano + Moro Taller de Arquitectura.” ArchDaily, ArchDaily, 7 June 2024, www.archdaily.com/1017433/nandi-house-fino-lozano-plus-moro-taller-de-arquitectura?ad_medium=gallery.

Khan, Zohra. “Casa Nandi in Its Muted Rammed Earth and Concrete Form Stands out yet Settles In.” STIRworld, STIRworld.com, 15 July 2024, www.stirworld.com/see-features-casa-nandi-in-its-muted-rammed-earth-and-concrete-form-stands-out-yet-settles-in.

The Kiln Tower for the Brickworks Museum

Boltshauser Architekten, founded by Roger Boltshauser in 1996, is a Zurich-based firm known for its focus on materiality, craftsmanship, and sustainable practices. Roger Boltshauser, a graduate of the Swiss Federal Institute of Technology (ETH Zurich), blends natural materials like brick and clay with modernist and vernacular traditions. His architecture reflects an environmental sensitivity, using low-impact materials to create buildings that are deeply connected to their natural surroundings.

© Kuster Frey, Zurich

The Tower for the Brickworks Museum in Cham, Switzerland, is a striking vertical addition to a museum dedicated to the region’s brickmaking heritage. The brickworks, which operates the museum, is the last surviving handmade brickworks in German-speaking Switzerland. The site includes a kiln, a drying shed, a clay pit biotope, residential buildings, and a museum, all tied to the region’s industrial past. The tower, which was completed in 2017, stands approximately 10 meters high, 13 meters deep, and 4 meters wide. Its tapered form and black steel entrance portal evoke a sense of transcendence, reminiscent of the ancient nuraghi of Sardinia or Oman’s tower tombs.

This unconventional structure won the prestigious Detail Award in 2022. It functions as an exhibition space, a working kiln, and an observation point, allowing visitors to experience the historical and material richness of the site while offering panoramic views from its rooftop platform. More than just an architectural addition, the tower is also an experimental exhibit, showcasing the innovative potential of rammed earth construction.

Situation plan – Graphic © Boltshauser Architekten

 

Floor plan, section, view, axonometry – Graphic © Boltshauser Architekten

The tower’s uniqueness lies in its method of construction using rammed earth, an ancient technique that has seen a revival in sustainable architecture. Designed in collaboration with students from the Technical University of Munich and ETH Zurich, under the expert guidance of Roger Boltshauser, the project also served as a hands-on self-build educational opportunity. The earthen modules were made of a mixture of fat clay and demolition rubble, as preparing loam on-site would have been too time-consuming.

One of the key innovations of this structure is its use of prestressed earth. Prefabricated rammed earth blocks were compressed on-site and stacked, each resting on a wooden plate that facilitated transport and construction. The integration of these base plates into the wall structure, along with grooves for tension cables, added strength and stability to the building. A weatherboard on each plate protects the earth from erosion and showcases the joinery principles. The use of horizontal supports made of trass lime mortar further reinforces the structure against erosion.

Prestressing earthen walls is a challenging process due to material creep and shrinkage, which can loosen the tension over time. To mitigate this, the blocks used in Cham were dried for a year, and additional steel springs in the tendons maintained constant pressure. Measurements indicate that the stability and hardness of the rammed earth increase under this pressure. The steel tendons, aside from their structural role, also add a visual rhythm to the compact tower, turning the technical necessity into an aesthetic element.

© Kuster Frey, Zurich

The tower is a testament to sustainable building practices. Its use of rammed earth—a material that can be recycled or reused—ties the building into the circular economy. The structure was built with the understanding that it would be dismantled after ten years. When this occurs, the rammed earth blocks can be easily reused, closing the loop in material usage and reducing waste. Compared to traditional concrete or brick construction, this method can result in a 40% reduction in embodied energy.

Moreover, the tower’s design aligns with the broader goals of reducing energy-intensive materials like concrete. In Switzerland, over 60 million tons of clay and earth are excavated annually, most of which is discarded in landfills. By using this resource in construction, the project makes a significant contribution to more sustainable building methods.

© Kuster Frey, Zurich

The Tower for the Brickworks Museum exemplifies Boltshauser Architekten’s commitment to materiality, sustainability, and craft. More than just a structure, it is an experiment in how traditional building techniques like rammed earth can be adapted for modern, sustainable architecture. The tower honors the industrial heritage of the brickworks while also embracing innovative methods, such as prestressed earthen construction, to meet modern engineering challenges.

Its combination of robust materiality and minimalist form inspires reflection on the connection between craft, place, and design. The structure also demonstrates how architecture can be part of a circular economy, with its materials poised to be recycled after its decade-long lifespan. Boltshauser’s work here stands as a reminder that thoughtful, context-driven architecture can not only tell a story through materials but also push the boundaries of what is possible in sustainable building practices.

References:

Boltshauser Architekten. (2022, March 18). Kiln Tower for the Brickworks Museum • Boltshauser Architekten AG. Boltshauser Architekten AG. https://boltshauser.info/en/projekt/ofenturm-fuer-das-ziegelei-museum/

Caballero, P. (2024, July 2). Kiln Tower for the Brickworks Museum / Boltshauser Architekten. ArchDaily. https://www.archdaily.com/972419/kiln-tower-for-the-brickworks-museum-boltshauser-architekten

Kiln Tower for the Brickworks Museum | Boltshauser Architekten | Archello. (n.d.). Archello. https://archello.com/project/kiln-tower-for-the-brickworks-museum

Walter, E. (2022, November 18). Kiln Tower in Cham. Detail. https://www.detail.de/de_en/ofenturm-in-cham?srsltid=AfmBOorkvFZgToXvWDRFMWlyDg4O5_SNjfN_gjXvs0bh4DE-C3lRFW5m

FRANÇOIS COINTERAUX: THE ARCHITECT OF THE ‘AGRICULTURAL PROLETARIAT’

Frontispieces to Cointeraux’s École d’architecture rurale (second edition, 1793). Façade of a ‘house of a decorated rammed earth house’ and the ‘same house made from the hands of a worker’.

FRANÇOIS COINTERAUX: THE ARCHITECT OF THE ‘AGRICULTURAL PROLETARIAT’ is an essay by Anja Segmüller who writes on the history of the French Architect Francois Cointeraux who is known for his focused attention on “the possibilities of ‘pisé’ (rammed earth) as a construction technique and to teaching the agricultural working class how to construct their own cost-effective, fire-resistant, and ‘dignified’ dwellings, founding several educational institutions”.

Read the essay at Drawing Matter.

Renzo Piano’s Emergency Children Surgery Center in Entebbe, Uganda

Renzo Piano is an Italian architect that has received numerous awards and nominations for his work, mostly qualified as “high-tech architecture”, a type of modern architecture that dares to innovate and defy norms. (1) His most famous design is the Centre Pompidou of Paris in which he works with high tech and sustainability through an emphasis on structural and technological elements. (1)

Vittoriano Rastelli / Corbis via Getty Images

Renzo Piano’s involvement in creating an Emergency children’s surgery center out of raw earth in Uganda continues that legacy of surpassing the norm. In this project, Piano contributed with EMERGENCY, a non-profit dedicated to offering complimentary, high-quality medical services to those in need (2). Such a partnership between visionary Renzo Piano and EMERGENCY therefore pushed for a project that guaranteed quality of biomedical devices, quality of building and a quality of life for those in the center(3).

Images courtesy of Renzo Piano Building Workshop & Studio TAMassociati, Milan Ingegneria

While the facility currently hosts 72 beds, a diagnostic centre, a laboratory for analysis, a blood bank, a pharmacy, as well auxiliary services such as a canteen and a laundry, it also hosts a healing and playful environment (2). In this center, play becomes part of a healing process as colorful walls populate the facility illuminated with the center’s large windows offering a view of either the heart of the complex: a large garden, or the site, which in total contain 350 trees planted (5).  

Image courtesy of Renzo Piano Building Workshop & Studio TAMassociati, Milan Ingegneria
The Center’s Courtyard. Image courtesy of Renzo Piano Building Workshop & Studio TAMassociati, Milan Ingegneria

 

 

 

 

 

 

 

 

 

 

Center’s Floorplan. Courtesy of ArchDaily.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

In this project, Piano and his team championed local tradition of building with earthen materials while also fusing it with his characteristic modern architecture seeking to build sustainably and efficiently.

Image courtesy of Renzo Piano Building Workshop & Studio TAMassociati, Milan Ingegneria

 

 

 

 

 

 

 

 

In a complex process of trial and error, architects and engineers of the Milan Ingegneria team researched theories and traditions in the region of earthen architecture, testing out experiments in the laboratory and on the construction site, to eventually come across the most performing mix for the project. The final mix was composed of: silty clay from the site, dried and cleaned in order to remove organic materials; aggregate to give the material compressive strength; Mapesoil, an establishing agent used to solidify the soil; a small amount of cement to stimulate the hardening process; inch-long (2.4 cm) polypropylene fibers to prevent tiny cracks from forming as the material shrinks; a fluidizing agent which made the mix easier to work with; and finally, a clear xylan-based coating applied to the outer surface of the wall to create a water-resistant layer stopping moisture from being absorbed or retained.(6)

 

 

 

 

 

 

A whole process of trial and error                                                                                                           Images courtesy of Renzo Piano Building Workshop & Studio TAMassociati, Milan Ingegneri

 

 

 

 

 

 

This rammed earth technique ensures proper humidity and temperature control(4), inducing thermal inertia. 

Image courtesy of Renzo Piano Building Workshop & Studio TAMassociati, Milan Ingegneria

This project by Renzo Piano is part of a broader movement that reimagines earthen architecture as a viable and valuable component of our modern world. It challenges the notion that traditional materials belong only to the past, showing how earth-based construction can play a key role in creating a more sustainable future. By integrating innovative techniques with time-honored methods, this approach not only honors architectural heritage but also addresses the urgent environmental needs of today, offering a path forward in the global shift towards more eco-conscious building practices.

Location: Entebbe, Uganda

Completion Date: 2021 

Project Owner: EMERGENCY NGO Onlus

Architects: Renzo Piano Building Workshop & Studio TAMassociati

Design team: RPBW – G.Grandi (partner in charge), P.Carrera, A.Peschiera, D.Piano, Z.Sawaya and D. Ardant; F.Cappellini, I.Corsaro, D.Lange, F.Terranova (models) – TAMassociati – R.Pantaleo, M.Lepore, S.Sfriso, V.Milan, L.Candelpergher, E. Vianello, M.Gerardi – EMERGENCY Field Operations Department, Building Division – Roberto Crestan, Carlo Maisano.

Consultants: Milan Ingegneria (structure); Prisma Engineering (MEP); Franco and Simona Giorgetta (landscape); GAE Engineering (fire consultant); J&A Consultants

References:

(1)”The Centre Georges Pompidou by Richard Rogers & Renzo Piano.” ArchEyes, www.archeyes.com/the-centre-georges-pompidou-by-richard-rogers-renzo-piano/.

(2)”Emergency USA – A Surgical Center in Uganda.” Emergency USA, www.emergencyusa.org/?doing_wp_cron=1727479427.1156270503997802734375.

(3)”Emergency Children’s Surgery Center.” Renzo Piano Building Workshop, www.rpbw.com/project/emergency-childrens-surgery-center.

(4)”Hospital Quirúrgico Infantil, Entebbe.” Arquitectura Viva, www.arquitecturaviva.com/works/hospital-quirurgico-infantil-entebbe.

(5)”Centre of Excellence in Paediatric Surgery.” Emergency USA, www.emergencyusa.org/prj/uganda/centre-of-excellence-in-paediatric-surgery/.

(6)”Children’s Surgical Hospital: A Scandalously Beautiful Dream.” The Plan, www.theplan.it/eng/whats_on/children-s-surgical-hospital-a-scandalously-beautiful-dream.