Concrete has been the dream material of modernity for more than a century. It can be moulded and formed; it can be polished, sculpted and bush-hammered; it can be smooth and shiny, or gritty and graffitied. But it can all too easily be mouldy and deformed, cracked and stained: a nightmare for those who have to live in the degraded, corner-cutting towers and underpasses of a degenerated modernist utopia.
Yet despite those dystopian associations, no material has been so consistently revived, recycled reimagined and reinvented in contemporary design. From hi-fi turntables to complex decorative relief wall tiles, there has been a move away from concrete’s more obvious applications to give mass, strength and stability to delicate or conceptual uses in which its associations and crafted qualities are allowed to shine through.
At October’s PAD London fair Will Shannon won the Moët Hennessy Design Prize with his conceptual work based around the history of a north London manufacturing site reusing old concrete for a table and a pendant light. Concrete has been taking off in lighting design in recent years, with Benjamin Hubert’s beautiful slip-cast, thin-walled concrete “Heavy” lights and Foscarini’s Aplomb range designed by Paolo Lucidi and Luca Pevere.
At the same time German designer Tim Mackerodt is working with a new kind of concrete for his “Falt” lamp and “Falt” stool – a fibre-reinforced material that is rolled out and folded manually into flexible moulds.
In each of these, the delight is in seeing something delicate or traditionally crafted made from a material as clunky as concrete. Among the most striking and innovative is Litracon, invented by Hungarian architect Aron Losonczi. Litracon is a concrete in which thousands of optical glass fibres are embedded in parallel but irregular strands, allowing the material to transmit light. The effect is extraordinary as light penetrates from outside, making silhouettes of passers-by appear on a seemingly solid wall.
That it can be used structurally is all the more remarkable: the fibre-optic strands reduce its load-bearing capacity by only a couple of per cent. What is so promising about Litracon is that it could inspire architects and designers to rethink the way buildings are made, to use concrete to create new types of wall and room, to make structure itself vibrant and decorative. It is an idea that reinvents concrete in such a way as to shake off those negative connotations of multi-storey car parks and city underpasses.
Then there is “BlingCrete”: a horrible-sounding but actually quite remarkable development by artist Heike Klussmann and architect Thorsten Kloster. This is a concrete in which tiny reflectors are set, acting like infinitesimal cats’ eyes to catch and reflect the light and to create luminous surfaces with applications that range from sculpture to traffic safety. Then, from Dutch designers Studio Molen comes “Solid Poetry” – a concrete surface that reveals hidden patterns when it gets wet, an idea that would enliven damp public spaces or bathroom floors.
Perhaps most remarkable of all is the recent suggestion by Dutch scientist Henk Jonkers of the Delft University of Technology that many of concrete’s familiar woes could be solved by implanting bacteria at the construction stage. These micro-organisms would lie dormant inside the material until water penetrated deeply enough to indicate that there was a problem – at which point they would activate and begin to repair cracks in the material in the way that bone heals itself when fractured.
Water penetration in concrete is a problem because it corrodes the steel reinforcement bars that hold the structure together: the bars subsequently rust, expand and cause the concrete to crack and spall. Nourishing themselves on the water and calcium in the concrete, the bacteria would grow and produce a kind of cement, plugging the gaps and filling the cracks, making it airtight again.
Scientists from Newcastle University are also developing a product along these lines, wonderfully named “BacillaFilla”. Within that name is also the niggling concern about what might happen if these microbes escaped and started to multiply, producing a solid world of organic concrete and filling every conceivable gap – but the scientists assure us that the microbes will remain resolutely in place.
More than the decorative uses of concrete mentioned here, this is an idea that could have radical, far-reaching consequences. Motorways, bridges, roads, pipelines and other major engineering infrastructure could be fixed in this way without the kind of disruption seen in London before the Olympics. Even more remarkable would be its use in earthquake zones, where there is no way to stabilise existing structures and often no resource to rebuild them. It is an idea that, quite literally, fills a gaping hole.
Edwin Heathcote is the FT’s architecture critic