We need new solutions for sustainable reuse, says Maria Brogren, but we should also look to the past
When I think about flexible buildings, I think of buildings that can be easily repurposed and used for something else. For a developer that builds and sells, the need for flexibility might be close to zero, but for a long-term owner, there might be a solid business case. Now, during the COVID-19 lockdowns, there is a lively discussion about how offices could be converted into apartments, and whether it makes sense to convert some residential buildings in the suburbs into business hubs to reduce the need for commuting, while allowing people to use shared facilities like printers.
But the change in use can also be minor, for example to combine two small flats into one. This concept is not new. In Sweden, this was one of the innovations of the Million Programme public housing project of the 1960s and 70s, where some of the apartment walls could be moved. But this feature has been forgotten during the last half century, so we do not really make use of it, which is a pity.
We need to analyze future trends before starting to develop a design. How do we expect the building to be used? How will the need change over time? How will the climate change, and will that have implications for the building? Which new technologies might have an impact on our building? Which new regulations? Then we consider how well the design can perform against these different scenarios. Can we make simple changes that increase flexibility and robustness without adding more than marginal cost? This will be an iterative process. We might want to increase ceiling heights or structural strength, but we might also end up using a lightweight wooden frame and a modular design that allows for add-ons.
There is another important part of flexibility that is often forgotten: the practical ability to deconstruct a building or parts of a building. How can we fit components together in such a way that they can be disassembled without being damaged? That’s a challenge for our engineers, especially since there are numerous other requirements, such as noise reduction, fire protection and energy standards. We need more innovation, and I see the potential to learn from other sectors. Standardizing components is key. There might also be forgotten solutions that we could revive, such as the old-fashioned timber work (“timring” or “knuttimring”) used for log houses in the Nordic countries.
From an environmental point of view, it is most important to be able to reuse materials with a high embodied carbon, such as a concrete frame. Wooden walls do not have such a large carbon footprint, and are easier to move. Digital technology allows us to rapidly test numerous designs and calculate factors such as material cost and carbon footprint. So future flexible building solutions might be a combination of post-war functional architecture, traditional construction techniques, and digitalization, automation and new materials.
Maria Brogren is head of sustainability and innovation at WSP in Sweden