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You can find the shownotes through this link.

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Are you interested in repurposing existing urban buildings and infrastructure?

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Our debate today works with the article titled Adaptability of buildings: A critical review on the concept evolution from 2021, by Rand Askar, Luís Bragança, and Helena Gervásio, published in the MDPI Applied Sciences journal.

This is a great preparation to our next interview with Manfred Schrenk in episode 374 talking about the importance of repurposing the urban context to the future.

Since we are investigating the future of cities, I thought it would be interesting to see the urban adaptability concept in a critical light. This article presents adaptability in buildings as a concept and its evolution over time, its various interpretations and the strategies and models that promote it.

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Welcome to today’s What is The Future For Cities podcast and its Research episode; my name is Fanni, and today we will introduce a research by summarising it. The episode really is just a short summary of the original investigation, and, in case it is interesting enough, I would encourage everyone to check out the whole documentation. This conversation was produced and generated with Notebook LM as two hosts dissecting the whole research.

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Speaker 1: Today we’re diving into the built environment. Buildings face constant pressure from urbanization, tech changes, climate impacts. They need to evolve.

Speaker 2: Absolutely. And that capacity to evolve to cope over their whole life cycle is key. But how we talk about it gets tricky.

Speaker 1: Exactly. Which brings us to our central question, is the difference between adaptability and flexibility in building design a really vital strategic distinction. Or are they functionally pretty much interchangeable in practice? I’m arguing that this distinction is necessary. These terms define change on fundamentally different levels, different timeframes, different functions,

Speaker 2: and I’m coming at it a bit differently. While, yeah, academics draw these lines sometimes in conflicting ways. Adaptability often feels like the bigger umbrella. Flexibility, I think is more of a strategy, a way to achieve adaptation. So making a hard separation strategically. I think it’s often superficial, especially since, let’s be honest, practitioners tend to use them synonymously.

Speaker 1: Let me lay out my position. For me, the real value of adaptation, the concept is in planning for those big, unpredictable, long-term transformations, think changing the entire function of a building or needing major structural mods, decades down the line, because the context shifted, that demands a completely different set of design principles compared to say, short-term flexibility, which is more about just easily rearranging internal walls or furniture. Adaptability tackles the 50 year problems. Flexibility is for the five-year adjustments.

Speaker 2: See, that premise doesn’t quite land for me because the moment you frame flexibility as just a tool for adaptability, it stops being some wholly separate concept, doesn’t it? I mean, sure there are distinctions people try to make about who initiates the change or the timescale. You mentioned others like Gore or Frica debate this too. But adaptability is fundamentally defined by the capacity to be modified. Flexibility along with things like scalability or convertibility. It’s just one of the main ways, maybe the most common way we enable that capacity. The end goal for both is extending the building’s useful life, right? So drawing these really sharp theoretical lines between the strategy and the outcome can, I think, actually muddle the design process when you’re trying to integrate everything.

Speaker 1: The actual design execution really forces you to separate these based on longevity. Take Stewart Brand’s sharing layers model, it’s a classic for a reason. It breaks a building down into layers that change at vastly different speeds. You’ve got the set the interior stuff maybe changing every five years. Then you’ve got the shell, the structure, ideally lasting 50 years or more. Planning for that 50 year structural change, which I’d firmly call adaptability, needs you to think about robustness, durability, maybe even overdesigning slightly to handle unknown future loads. That approach is functionally, materially and financially separate from planning the five year interior churn, which is flexibility. They require different thinking, different materials, different budgets. That’s an

Speaker 2: interesting point about brands, layers, though I might frame it slightly differently. Aren’t things like flexibility, scalability, and convertibility often presented precisely as the strategies needed to manage change within those different layers? Think about modularity. For instance, a modular system makes interior reconfiguration easy. That’s flexibility, right? But good modularity also lets you potentially reuse or repurpose major building components later on, which sounds a lot like enhancing long-term adaptability. So if one strategy like modularity clearly serves both masters, how practically useful is insisting on that strict conceptual separation? Doesn’t it break down?

Speaker 1: I think the conceptual clarity is vital because it guides those crucial early investment decisions. Some useful definitions like those hinted at by till and Schneider suggest. Adaptability often deals with larger scale changes driven by external factors, climate adaptation, new regulations, big market shifts. Flexibility then handles the internal user-driven needs, changing office layouts, tenant preferences. Optimizing space day to day. Making that distinction helps designers argue for where to put the money. You invest heavily in durability for the structure, the long life element designed for adaptability, and then you design the interior spaces for loose fit and frequent easy change. That’s flexibility. It dictates where robustness matters most, versus where ease of modification is paramount.

Speaker 2: I’m sorry, but I just don’t quite buy that clean separation, mainly because the academic literature itself really struggles with that neat internal, external, or user system distinction you mentioned. You can find scholars arguing it both ways, sometimes directly contradicting each other on whether flexibility or adaptability relates to internal versus external drivers. Plus the fundamental goal extending the building’s useful. Life is identical for both. Look at practice concepts like the open building approach, which are all about achieving design for adaptability or DFA. They deliberately integrate a durable, long lasting support structure. The base building with highly flexible infill components. It demonstrates that success comes from seeing these as inherently linked parts of a single adaptive system. Not as conceptually separate battles to be fought.

Speaker 1: I still believe the necessity of the distinction is most clear when we apply models like shearing layers in practice. Adaptability forces that long-term thinking about the structural core, the elements that must endure for potentially half a century or more. It demands specific foresight about worst case scenarios, systemic changes. It underscores that these huge long-term modifications require a fundamentally different design methodology. Then the short term spatial adjustments covered by flexibility.

Speaker 2: That’s a compelling way to frame it, definitely. But have you considered how many enabling strategies, think about standardization of components, for example, actually serve to enhance both flexibility and adaptability at the same time? Standardization makes quick fitouts easier flexibility, but also facilitates component reuse and larger retrofits later adoptability. Ultimately isn’t the key objective. Defining and maximizing the building’s overall adaptive capacity to stay useful as requirements change. Whether we precisely label each specific intervention as flexibility or adaptability might be less critical than ensuring that capacity exists. There’s clearly still a lot more work needed to bridge this conceptual discussion into consistent practical design guidance.

Speaker 1: Agreed. It highlights the challenge of translating these important theoretical distinctions into unified action on the ground.

Speaker 2: Absolutely. It’s a complex interplay and understanding these different facets is crucial, even if the labels remain a point of debate.

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Episode and transcript generated with ⁠⁠Descript⁠⁠ assistance (⁠⁠affiliate link⁠⁠).