‘En Route’: a bio-concrete that is sustainable and strengthens over time

In a world that is still learning the true impact of widespread ecological changes, we are constantly confronted with the consequences of extreme human intervention. We have to now deal with altering biospheres on a variety of different levels. One of these levels is the rising concern of invasive species that are altering habitats and causing ecological and environmental damage. There are growing efforts across farmlands and various landscapes to curtail the effects of these introduced species on the indigenous environment. In the UK, both Japanese Knotweed and the American Signal Crayfish have been at the centre of widespread removable effort. Designer Brigitte Kock and architect Irene Roca Moracia have experimented with a strategy to utilise the by-products of this removal drive to create a range of new bio-concrete tiles. By creating scalable material processes, this innovative new material adds a monetary value to the removal efforts, in order to facilitate the restoration of the natural biodiversity.

The duo speaks with STIR about their experiment and collection, called En Route.

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Devanshi Shah (DS): I am curious about the title of your collection, En Route. Please tell us how did you select the name.

Brigitte Kock (BK) and Irene Roca Moracia (IRM): It’s a collection made with the biomaterial of ‘travelling species’, albeit the invasive species have usually been brought by humans initially, they come from far and are spreading wildly in the UK.

DS: What inspired you to use waste from invasive species treatments as one of your raw materials?

BK and IRM: Just before we started the project, Brigitte saw a fish she never thought to see in real life, one that she had only seen in her favourite children's book on deep sea creatures. Whilst trying to find the English term, the Lionfish went from ‘mythical’ to ‘so-overly-abundant-it’s-destroying-the-endemic-species’ in a matter of minutes. The experience left quite the impression, and after sharing the story we made the decision, very early in the project, that we wanted to create a material that had a bigger positive impact – a regenerative material. Of course, working with exotically sourced waste would defeat the purpose of the project, so we instead looked at local invasive species harming the UK environment, since we are both located in London. We soon found out that the UK government spends about £2 billion annually to manage invasive species, roughly £1.6 billion of which goes to the removal of Japanese knotweed alone!

DS: Your project specifies three materials you experimented with, namely concrete, stone and glass. Could you tell us a little bit more about how each one works?

BK and IRM: We started looking into how to incorporate the by-products originated from the removal of the two invasive species into the creation process of an architectural material. We started off by making many different samples of 10x10cm, trying different methods like indeed, making glass, creating stone through compression and water bathing. In the end the samples using ancient Roman  concrete techniques worked best, so we continued to make the collection with that method.

DS: You reference using ancient Roman techniques, could you explain that in detail?

BK and IRM: There is no clear recipe that has survived over time but a principle with certain variations according to the use or location of the Roman structures built. At present, there is no way of ascertaining what water/cement ratios the Romans used. Romans used volcanic ash or wood ash as binder in their concrete constructions. We use Japanese knotweed ash and root powder. Their aggregates tended to be much bigger than what we normally use now, they added broken bricks and rocks to the mix, here we use American Signal Crayfish shells. We have followed their principles and created a bio-concrete with different recipes variations. We have played with the ratios to obtain really strong results.

The final colour and textures depend on curing times and aggregates chemical reactions with the binder and the water. This part is really close to what Romans did — they knew how to incorporate different elements to the curing process to obtain different results, for example concrete structures that can resist the corrosion caused by sea water. We have submerged Roman structures that have survived. Our modern concrete can’t perform at that level, it deteriorates rapidly in saltwater and over time. Just like the aggregate, our binders have an organic origin, as much of the sands and rocks the Romans used or modern cement, we can’t forget that limestone often contains fossils. So, our bio cement is our own interpretation of what we could achieve following the Roman principles of concrete production. 

DS: Have you had the opportunity to test the usability of this product? What potential uses do you foresee?  

BK and IRM: In luxurious interiors it would be great if this could replace less sustainable and non-regenerative materials, like concrete or limestone. Having an alternative to the current unsustainable Portland cement can completely change the environmental impact that construction has. A bio-concrete like this one could be used for any kind of finish at the beginning without compromising structural elements until it is properly tested and controlled. But it could be used for many things because we are able to cast it into shape - from tiles to furniture. Since it can be poured into any shape, we would like to try to use the material to create furniture. We would like to experiment with the shapes and thicknesses to understand how the material can work and furniture is a great field to do that without compromising anyone’s safety. 

DS: How does this collaboration feed into both your individual practices? Is there an overlap between your individual practice and this project?

BK: My practice revolves around 3D-printing of textile and parametric pattern drafting. Ultimately, I am looking into how we would be able to print our entire wardrobe. Since the current plastic filaments don’t really have the soft feel silk or wool do, I am interested in researching and creating innovative materials. During my MA Material Futures at Central Saint Martins, I was inspired by Carole Collet and Michael Pawlyn to start thinking beyond sustainability. This project has been a great opportunity to combine regenerative design and material innovation.

IRM: I am an architect and design researcher working with spaces generated by the overproduction crisis. I question the production and consumption of architecture in European countries, from the point of view of sustainability and social inclusion. For over two years at Central Saint Martins, I researched on how these systems of production work. I presented a furniture collection that reintegrates discharged construction materials with a functional purpose. I believe that the scale in which we play with furniture pieces, or in this case with materials, in interiors allows us to test complex ideas around sustainability and social issues in a faster and more dynamic way than architecture. This material is the first step towards regenerative architecture and product design. 

DS: Could you share your personal insight or anecdote about the process of creating this collection?

BK and IRM: This project happened during lockdown, so we had to work in Brigitte’s kitchen. As our material samples had to dry in the living room/kitchen, the humidity levels were impossible to control (which during the first 36 hours of the curing process should be stable), we had to build a drying rack outside the apartment with a sign that said ‘Drying Artwork – Don’t touch!’. It’s great to see that there is no need for fancy workshops or tools when you really put your mind to it, inconvenient for sure, but creativity solves most of the ‘problems’ we had encountered.

This project was developed as part of LVMH Material Innovation: A Maison/0 project with design and architecture graduates from Central Saint Martins UAL. Project led by Professor Carole Collet, Director of Maison/0, the Central Saint Martins LVMH Sustainable Innovation Programme.