The circular economy could make demolition a thing of the past

Most of us are already quite comfortable recycling our household waste. In Spain, for instance, millions of tonnes of packaging are processed every year, but did you know that buildings and their materials can also be recycled, or that an entire building could be completely dismantled and reassembled?

Formula 1, often a laboratory for innovation, offers us a real-world example of this in the form of the Red Bull team’s “pit box”, known as the F1Holzhaus – literally, “the wooden house”. It made its debut at the 2019 Spanish Grand Prix and has been the team’s “home” in Europe ever since. Before every Grand Prix, fourteen workers assemble its 1,221 square metres in just 32 hours, and then dismantle it in less than a day.

This building reflects a change in the conception of construction, which has to be increasingly committed to sustainable buildings that can be adapted, modified and reused.

2.2 billion tonnes of waste

The construction industry is one of the largest producers of waste, generating around 2.2 billion tonnes per year globally. In Europe, it produces about 450 million tonnes, 40% of the continent’s total waste.

More than 90% of construction waste comes from demolition, but waste is also generated on-site – mainly as leftover or broken materials – and during manufacturing. The latter goes largely unnoticed, but we can visualise it in one stark statistic: the wooden beams in a building are usually just 20% of the original wood taken from source. The remaining 80% is lost as production waste in the form of sawdust, scraps, discarded parts, and so on.

This reveals the limits of the linear model – production, use, disposal – that still predominates. To counter this, the circular economy presents an alternative: designing for disassembly. This replaces demolition with systematic disassembly, meaning components can be recovered and reused.

This paradigm shift – from a single-use mindset to one of “reduce, reuse, recycle” – is already common in other fields. It is now starting to take hold in construction through various global initiatives that seek to integrate these concepts into safer, more sustainable and more durable buildings. They show how this can be achieved through conscious design, based on concepts such as modularity and standardisation.

This is coupled with carefully designed reversible joints, which allow disassembly without damage, as well as existing digital tools such as “material passports”: digital documents that locate and quantify the products and materials in a building, which can greatly simplify their future reuse.

Upcycling construction waste

Of course, the solution is not only to dismantle and reuse what has already been built. In this change of model, from linear to circular, it is also crucial to transform waste into resources. This means going from a “cascading” model – traditional recycling where materials are used to make products of lower value (such as shredding wood waste to make chipboard) – to “upcycling”, where discarded materials are given a new life as items of higher value or utility.

There are already specific ideas for applying upcycling principles in construction. As we have seen, almost all of its waste comes from demolition, but what if that construction waste didn’t go to landfill, and was used to make a new building instead?

That is the area that Spanish designer Lucas Muñoz explores. Look at the furniture and lamps in the restaurant MO de Movimiento or the CoLab de Sancal (both in Madrid) and think about how they might be made, from what materials. it might not look it, but every item is made from the waste of the previous premises.

Action is also needed on production waste – the aforementioned 80% of lost wood. The Spanish PRISMA Project aims to manufacture high added value products, such as building blocks made from sawmill waste that would otherwise be burnt or shredded and turned into low-value chipboard.

By upcycling these materials, waste becomes more valuable, and this has spurred the development of new, imaginative solutions. Just look at the façade of EcoArk in Taiwan, which is made of PET plastic soft drink bottles. It can also, of course, be completely taken apart and reassembled.

The EcoArk building in Taiwan, made from 1.5 million PET bottles, is the world’s first building made entirely from waste. Richie Chan/Shutterstock

Reuseable fences

In truth, this idea is nothing new. We have been doing it in various forms for generations, often out of pragmatic necessity or tradition rather than innovation.

We can end here with another example: the running of the bulls during San Fermin, in Pamplona. The fences that protect the public from stampeding bulls throughout the run’s 848 metre course are made from wild pine, sourced from the neighbouring Roncal Valley.

The 900 posts, 2,700 slats and 2,500 wedges are not produced and thrown away every year – once the festivities end they are dismantled , then stored to be re-erected the following year. Usually, less than 2% of the material has to be replaced from one year to the next.

This demonstrates how circular management based on ancestral knowledge is now the future of construction. Examples like this can guide the way to a more efficient and sustainable use of resources.

This article is also published on The Conversation. illuminem Voices is a democratic space presenting the thoughts and opinions of leading Sustainability & Energy writers, their opinions do not necessarily represent those of illuminem.