Can We Eat Buildings? Thoughts About Edible Buildings Made of Earth
Can We Eat Buildings? Thoughts About Edible Buildings Made of Earth
The use of earth-based materials appears in two practices throughout history: in the construction of buildings and – far less commonly known or conclusively understood – in certain dietary consumption patterns. To put it simply – soil, the most important nutrient collector on earth, can be used for both building and for eating.
For building practices, earth materials are among the oldest known to mankind, comprising structures that date over millennia and still sheltering approximately a third of the world population[1]. It is a vernacular material in the global south as it is in Germany, France, and the UK with more than 500,000 earth-based dwellings can be found just in Western Europe[2]. Meanwhile, as regards earth eating, both cultural practices and individual behaviors involving the ingestion of earth materials have been recorded for centuries across the world: in Africa, the Carrebians, the Middle East, Ancient China, and Europe. “Recipes”, so to speak, such as the Calabash Chalk, use clay-rich soils, whether for religious rites, as medicine, or to satiate a regular craving[3].
Despite many similarities and almost parallel historic and geographic routes, to the best of our knowledge, the two phenomena have never been compared or combined. The [EAT ME BUILD ME] project aims to fill this lacuna by examining parallel histories and converging them through looking into the mineralogical structure of earth materials.
The installation, forthcoming as part of the 2022 Tallinn Architecture Biennale, comprises of a matrix arrangement from buildable to edible earth elements. Our soils were harvested from a recycling quarry located in Goshen, NY, an hour from Manhattan. We tested the soils for their particle size and mineralogical content, to inform the elements arrangements on the scale from buildable to edible.
On the buildable side, digitally and manually fabricated bricks showcase the state-of-the-art in manual and digital earth construction while introducing bio-based reinforcement additives for enhanced strength. On the edible side, earth cookies, chalks, and capsules are presented, replicating traditional recipes as well as offering modern interpretations for using earth as a food supplement. On each side of the matrix, a video depicting buildable and edible earth practices, as viewed from a Western point of view.
The Western Bias
Both historical practices – of using earth as a buildable and edible substance – have experienced negative interpretations. Earth building has been pushed aside during the colonizing processes of industrial modernization due to the introduction of industrialized materials such as Portland Cement[4]. As the dictates of architectural modernism and developmentalism (postwar international development) took root around the world, the desire to replace earth––a labor-intensive, highly variable and difficult to standardize material––with mass-produced parts cohering with global economies of scale relegated earth-building to the sidelines. Earth building materials have gained a negative perception as “dirty” and the poor mans’ choice for housing, as shown in a previous global perception study studied by Ben-Alon[5].
In the case of eating earth, perplexity – both from outsiders to a cultural community and sometimes from members within the same society – has long led to associating it with the practice of Geophagia: a pathology or a psychiatric disorder of unconstrained urge to consume earth, mud or dirt. Not only was it considered harmful to the consumer health and digestion system, but the interchangeable use of “earth,” “ground,” and “dirt” also invoked notions of excrement, filth, and the dangers of decay. Our current-day biases against the idea of earth-eating can also be traced to the perceived causal link between poverty and the practice – in short, the bias that eating earth can only be a desperate last resort in the face of food scarcity.
However, attitudes have begun to shift regarding these phenomena: in the case of building with earth, the catalyst has been the urgent wake-up call due to the climate crisis and the need for more sustainable building practices and materials. In the case of earth-eating, a growing body of scientific evidence show that eating earth can be traced to evolutionary advantages and can provide specific health benefits.
The Mineralogical Common Ground
Soil is formed due to natural weathering of rocks and it takes millions of years for the formation of soil to occur. Within the soil, clay minerals are the essential component for supporting the plant growth. In burnt bricks, it is not possible to get back the natural clay minerals from the burnt clay, unless allowed to undergo weathering for millions of years.
What parts of soil can be used for eating? Surprisingly enough, both the buildable and edible parts of soil share a common mineralogical base: clay. Regardless of their geographic local or cultural habits, traditional earth-based recipes come with clear instructions on what type of Soil to use and where to source it from. They all have in common the use of clay-rich soils, which includes minimal organic micro-bacterial activity. Although in everyday speech, “clay,” in its plastic, moldable state, is associated with mud and dirt, in its particle state, when not suspended in water, it looks much like other particles of rocks that humans use as spices.
On a metabolic chemistry level, clay counts as an adsorbent mineral. Clay minerals consist of about 15 ordinarily classified minerals that belong to three main groups: kaolin, illite, and smectite. As such, an important concern when considering the construction uses and health benefits of clay is the same as with other minerals, which is to say, how stable, labile, or bioavailable is the mineral (i.e. able to be absorbed and made useful for the building and by the body). Suitability of clay minerals for eating and building with earth share important similarities: for both practices, Kaolin have been a favorite. Kaolin was shown to reduce nausea and poison-related sickness and death[6], while also being an ideal clay mineral for earth construction – water is less able to penetrate between the molecular layers; thus, it exhibits higher compressive strengths and reduced swelling on wetting[7].
The [EAT ME BUILD ME] project
As an experiment, the [EAT ME BUILD ME] project is a first-of-its-kind attempt to expose the similarities and converge the almost parallel historical and geographic routes of building with and eating earth. It speculates a larger scope of building supply chain mechanisms, where earth-based materials (namely, mud, or dirt) are perceived not as an ineffectual matter, but as a multidimensional resource that can be used for both a shelter and a meal, thus offering a futuristic perspective to the growing field of knowledge that investigate healthier substances in building materials. To further stretch the boundaries of building materials field we speculate and ask questions such as: Can we develop edible building components that are customized to our mineral and nutrient deficiencies? Can readily available soil be used as both buildable and edible substances?
This experimental installation tests ideas and beliefs regarding the nature/culture divide that governs so much of our existing paradigms of environment. While it literally maps raw soils for their buildable and edible potencies, the experimental setup also produces a map of these various ideologies and their tensions, towards the current reformulation of our being in the world.
the [EAT ME BUILD ME] project is both a tactical and conceptual exercise. It aims, on the one hand, to examine and re-discover supply chains of readily available earth-based materials as both building and nutritional substances. It offers a unique perspective on human metabolism and nutrition possible by ingesting our surrounding building assemblies. This speculative text and installation aim to radically suggests that possible earth- and bio-based assemblies can be submerged within building facades as natural, healthy, nontoxic, and presumably – edible building mass. As opposed to green facades where food is grown upon fabric systems or containers, the uniqueness of this research stems from its use of agricultural nutritional substance – namely farm to building and building to table as a source for minerals, nutrients, and superfoods within the building itself.
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[3] Young, S. L., Sherman, P. W., Lucks, J. B., & Pelto, G. H. (2011). Why on earth?: Evaluatinghypotheses about the physiological functions of human geophagy. The quarterly review of Biology,86(2),97-120.
[4] Martinez, D. J. S. (2017).Concrete Colonialism: Architecture, Urbanism, Infrastructure, and the American ColonialProject in the Philippines(Doctoral dissertation, Columbia University).
[5] Ben-Alon, L., Loftness, V., Harries, K. A., & Cochran Hameen, E. (2022). Overcoming the Perceptual Gap: Worldwide Perceived Comfort Survey of Earthen Building Experts and Homeowners. In Construction Technologies and Architecture (Vol. 1, pp. 521-528).
[6] Liu, Y. L., Malik, N., Sanger, G. J., Friedman, M. I., & Andrews, P. L. (2005). Pica—a model of nausea? Species differences in response to cisplatin. Physiology & behavior, 85(3), 271-277.
[7] Narloch, P., Woyciechowski, P., Kotowski, J., Gawriuczenkow, I., & Wójcik, E. (2020). The effect of soil mineralcomposition on the compressive strength of cement stabilized rammed earth.Materials,13(2), 324.
