In Belgium, no less than 36 million tonnes of earth are excavated every year on building sites. Two million tonnes in Brussels alone. That material is not easy to keep, store and transport, so 60 per cent of it is thrown away as waste. Since 2019 BC materials, a spin-off of BC architects and studies, has been recovering the raw earth from the ground to convert it into new building materials. That is why the designers’ collective built a small storage and production hall on the site of Tour & Taxis in Brussels. BC’s ultimate goal is not only to offer the manufactured loam bricks for sale, but to change no less than the entire conventional building culture.
In 1983 the Anglo-American historian Kenneth Frampton wrote his by now seminal essay ‘Critical Regionalism: Six Points for an Architecture of Resistance’. Frampton valued not only the importance of an embedded architecture within the given topography of a particular site, but also its sensibility towards local resources and materials: ‘In a climate where culture becomes a global concept, a certain form of resistance seems to develop that finds added value in the locality of a given.’ [i] While the current ecological transition confronts the architectural profession with an economy of means, Frampton’s plea for local materials, tectonics and tactile architecture is becoming more and more appealing if not necessary.
The work by the Brussels-based collective BC architects, studies and materials is in this context remarkable. Since 2012 BC has explored the relation between architecture, material production and the act of building. In both Muyinga (a small community in Burundi) and Edegem near Antwerp, they realized their first small public buildings with locally produced and manufactured materials, keeping a short supply chain of expertise and labour. To achieve their objectives, BC needed to bypass regulations proscribing the execution of the designed project by the architect. BC operates through three different entities: BC studies, a non-profit organization, elaborates specific analyses for the site, in close collaboration with local craftsmen; BC architects designs the projects and supervises them; BC materials, a cooperative society founded in 2019, expands the analyses of BC studies and produces building materials.
The polluting character of the construction sector lay at the origin of BC materials. By collecting raw materials from Brussels construction sites, BC explores the possibility of urban mining. ‘Every year, some 36 million tons of earth are dug up in Belgium, of which 2 million come from Brussels. Forty per cent of this excavated earth is reused for road construction and major infrastructure works, but the earth-moving sector has trouble dealing with the remaining 60 per cent’, clarifies Ken De Cooman. Through an agreement with the earth-moving sector in Brussels, BC recuperates sand, loam, clay and gravel in order to turn them into new building materials.
When BC was looking for an affordable production site in Brussels, it was forced to turn towards an unoccupied plot in the Brussels Canal Zone that could be rented for a period of four years. Avenue du Port 104 is an intriguing place. It testifies to everything the Brussels Canal Zone has to offer – a sea breeze, industrial hangars, trucks riding on and off, and leftover space. In the midst of this eclectic association of nature, industry and materials, BC realized a small, somewhat robust but intriguing building: a storage and production site for materials. Built as a totally demountable structure, the hangar is made almost entirely of circular materials. Second-hand concrete tiles placed on a bed of construction waste make up the floor. Two second-hand containers function as load-bearing points on which the roof is positioned. Second-hand Legio building blocks were used to create the storage spaces for sand, clay, loam and gravel. Stacked on top of each other, the Legio blocks require no joints, which makes them easily demountable. With straps and bolts, 25 wooden Steico I-beams are attached to the containers and hold up the corrugated iron sheet roof. The BC materials production site has room to store products, contains a drying space and has a polyvalent workshop area where new composites can be explored and tested. Three products are on sale by BC materials: the Brickette (compressed earth blocks), the Brusseleir (raw earth plaster), and the Kastar (a clay concrete).
BC are not the only ones working with compressed earth, clay or loam. The German Martin Rauch has been working with loam as a construction method for a long time. In 2000 he realized the Chapel of Reconciliation in Berlin, but BC is currently the only one that mines urban construction sites for material resources. The circular economy has become an important criterion in many of the tenders in the Belgian capital. Regularly invited to join a team, BC contributes with its knowledge and know-how. The goal of BC is not only to sell earth-building materials but to change the building culture of a somewhat conservative building sector. That their expertise might also lead to atmospheric quality and tactile architecture becomes evident in their latest projects. However, their current manual and low-tech production techniques are not efficient enough at the moment for large-scale projects. The architects are now in conversation with the bigger cement-block producers in order to discuss and elaborate strategies of collaboration and production with earth resources as an input. In addition to current trends for bioclimatic building (conceiving of buildings with a low to zero carbon emission percentage) and circular building (conceiving of buildings with recycled materials), BC introduces bio-based building and stresses the importance of building with natural materials. They translate Frampton’s critical regionalism into a contemporary agenda combining circularity of materials with material innovation.
[i] Kenneth Frampton, ‘Critical Regionalism: Six Points for an Architecture of Resistance’, in The Anti-Aesthetic: Essays on Postmodern Culture, ed. H. Foster (Washington: Bay Press, 1983), 16–30.
