Long-lasting structures are one of the best means at our disposal for reducing the environmental impact of the built environment – perhaps the best of all. The longer a building lasts, the more economically its resources are used. Over time, it requires less material proportionate to its usage, requires less energy to demolish and generates less waste. From this perspective, a historic building like the Pantheon in Rome is a perfect example of sustainability, one of the most environmentally responsible buildings ever built. True, it was built with huge amounts of opus caementitium – an early form of concrete – which means its construction was far from climate-friendly. But that barely matters any more. The point is, the Pantheon has stood for almost 2,000 years, which means that it has required remarkably little grey energy when you look at its entire lifetime. But it’s not just the great Roman monuments: every building that stands for more than 100 years will have a better energy footprint than the most efficient, environmentally sound passive house built today. We need to build buildings to last. They have to be used until the end of their life, and that end must be extended as far as possible.
Not only must the buildings themselves be used multiple times and for as long as possible, but so too must the materials from which they are constructed. A simple, clever and radical strategy for using building materials sparingly is to recover them from abandoned buildings and reuse them.
This strategy comes with a long history. In the past, raw materials were rare and expensive. Ancient civilisations invented techniques for reusing construction elements following demolition, including terrazzo – a mix of limestone, cement and aggregates, mostly marble chips. Flooring techniques like the intricate “Roman pattern” or the more freestyle “Palladiana” reused remnants from stone panels that were not suitable for classic regular patterns. It is this tradition of economising that we need to rediscover.
While the reuse of building materials saves resources and reduces waste, it still requires energy. For an even better environmental footprint, it is not just building materials that we need to reuse, but whole structural components.
The reuse of structural components in new builds also has a long tradition. Historic cities were often built on the foundations of older urban structures. Monolithic Roman columns, largely chiselled from high-quality stone, were reused in early Christian basilicas – including the Lateran Basilica and the predecessor to St Peter’s in Rome. Columns of different heights were balanced out with pedestals or capitals, which were often recycled as well. This practice reached its peak in the Mezquita of Córdoba between the 7th and the late 9th centuries, with 856 columns made of granite, marble, jasper and onyx – primarily from various ancient Roman structures – used to support the horseshoe arches that bear the weight of the enormous prayer hall, creating an imposing, neatly subdivided space.
And it wasn’t just the prestigious, landmark buildings; for a long time normal houses were palimpsests of new and found elements. For reasons of pragmatism alone, no one would think to simply throw away a solidly constructed door, a functioning window, a stone threshold or a cornice. While the primary value of these elements is economic, they often have an artisanal, artistic and emotional value as well.

But for reuse of materials and construction elements to be viable, they need to be recoverable. Recovered items retained and reused in the past didn’t just have a material value, they had an artistic value as well – in fact we may well conclude they were often reused less for practical reasons of economy than for their aesthetic refinement.
These days we tend to reuse functional elements, such as windows, doors, floors, sinks and taps. Their reuse is driven in part by the fact that old products tend to be better made than new ones, and often have a greater appeal. But new builds need to be configured for the reuse of building materials and structural elements as well. This means using as few materials as possible and ensuring that they are pure, unmixed and untreated – without coatings or paint; structural elements that are easy to disassemble and reuse; simple, solid artisanal details; mechanical joins in place of bonding or silicon sealant. When we design a building, we need to be thinking not just about its inception – its birth, if you will – but also its lifetime and its end of life.
This architecture of sustainability doesn’t exist yet – it has to be invented. And enabled. There are plenty of obstacles: the building materials and components offered by the construction industry are not designed for longevity or multiple use, nor are the building laws and regulations, which prevent many sensible ideas from being implemented. The work required to produce high-quality recycled structures is expensive – but the cost of disposing of construction waste is almost negligible compared to its environmental impact. This has to change – radically.
But even more than that, we need to change the widely held view that the old, the used and the reused have a lower functional and aesthetic value than the new. It is this myth that drives our consumer culture so persistently. So too the idea that our contemporary lifestyle can only be expressed in extravagant, wasteful architecture. In fact the opposite is true. A truly modern architecture that not only recognises the demand for sustainability but also seriously embraces it will be designed to last – and economical with the resources it requires. This will result in a new expression of simplicity, an archaic quality even, which is creatively derived from the old.