Writing on the walls

Right now, there is some exciting experimentation into how concrete structures might be reused, and I’ve been thinking a lot about how architecture might evolve in a more circular economy. If you’re going to adapt or reuse a building or its materials, you need to know what’s there in the first place. Recent projects have found useful information in company archives and even back issues of Concrete Quarterly.

But how do we communicate more complex data to future project teams – especially when concrete buildings can stand for well over 100 years? Development of material passports is one area of focus, but we can also think about the role the building itself plays. Should we express the joints between elements to show how they could be taken apart, for example? We already do this to some extent: with a post-tensioned slab, the location of strands is often sprayed onto the soffit before the suspended ceiling goes on, to show where it can be cut.

At the moment, the main way of passing on this kind of information is via a handover report, physical or digital – and easily lost over the long term. We can embed e-tags within the building, but we can’t be sure that the technology to scan them will still be around in the distant future. Perhaps there could be an evolution of technical graffiti, with key information written in designated locations, like over the main entrance. But, as we know from material passports, there’s an enormous amount of information to communicate. There’s also a question about how much people will be prepared to rely on a voice from the past – who would trust that data? Decisions about reuse will always be based on current analysis.

There are a growing number of scanning tools that can identify materials and quantities as part of pre-demolition audits, but the process is greatly facilitated if there are some clues to start with. To me, that makes the architectural expression of a building even more important. After all, aesthetics is essentially a form of communication, data that we can read intuitively.

Of course, architects have always thought about how to make a building legible to its users, so this is really just a new twist on an old problem. It certainly doesn’t mean we need to return to brutalism, which is just one response and a very particular language. As the projects in this issue show, a structure doesn’t have to take centre stage to be legible. At Pitman Tozer’s Farrimond House in Barking, the only hint of its hybrid precast and in-situ frame are the panels that encase the stairwells.

Stanton Williams’ student housing for Emmanuel College, Cambridge hides a maze of transfer structures in its basement. At PI59 in Amsterdam, a 1970s slab block has been glazed and wrapped in a terrazzo-like precast facade. Perhaps in 60 years, this will be replaced and the building reinvented again for another new age. The interaction of sustainability, circularity and architecture raises so many fascinating questions for design teams to explore. I can’t wait to see what answers we’ll come up with.

Elaine Toogood, Director, Architecture and Sustainable Design, The Concrete Centre