ULiège, Factory of Possibilities

Sophie Trachte : building the transition

Let's dare the impossible!

At a time when global warming is forcing us to be more energy sober, Sophie Trachte, an architect specializing in sustainable and circular building renovation, sees a tremendous opportunity to rethink our way of thinking, so that construction and renovation finally rhyme with eco-responsible management of resources and waste.

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Whether it's to keep warm in winter or stay cool in summer, our buildings are one of the biggest consumers of energy. This is why the European Union is forcing its member states to drastically increase the rate of building renovation by 2050. However, " these renovation operations will require large quantities of both materials and energy, and generate a considerable amount of waste," warns Sophie Trachte, professor of sustainable, circular and performance construction and renovation at the Faculté d'Architecture of the ULiège University. Achieving an EPB A (Wallonia) or C (Brussels) should not be a sacrosanct objective that comes at the price of a dramatic environmental impact in terms of resources. "

It has to be said that the researcher knows these issues well. And it's because they had long been on her mind during her first life as an architect that Sophie Trachte returned to university, with the idea of finding answers herself. " During renovation projects,I have too often witnessed heavy destruction, with containers filled with materials considered as waste, even though they were still in very good condition ", she recalls.

Aware that, like her, others need to ask themselves the same questions, the architect-turned-researcher specializes in the sustainable and circular rehabilitation of existing buildings " so that they are once again usable/inhabitable, while meeting modern comfort requirements" She is also interested in the development of new materials from construction waste, as well as the principles of adaptability and reversibility in building construction. in my opinion, architects have a preventive role to play upstream, to avoid as much as possible the production of waste at the end of a building's life," she says. That's why we're working on new reversible construction systems that facilitate future dismantling. It's essential for me that my research work percolates down to the sector to help it transform and move towards greater sustainability. "

Reactivating our collective memory

For Sophie Trachte, the renovation targets imposed by the European Union are the perfect opportunity to bring bio- and geosourced materials, with their multiple properties, back into fashion. wood, plant fibers, earth and clay are all bio- or geosourced materials that have been with us for over 10,000 years," she explains. For this reason, I'm firmly convinced that they are part of our DNA and our collective unconscious, and I'm keen to reactivate this memory, by using them in traditional or new and innovative building solutions. "

According to the researcher, these materials are "balanced". First of all, they have many interesting physical and technical properties, particularly in terms of hygrothermal behavior. Secondly, they enhance the value of local territories, resources and know-how. Finally, they support our objectives of carbon neutrality by storing carbon in their organic matter over the long term. They also support our circular economy objectives, as they are often by-products and co-products of agriculture or forestry, and can be minimally processed and reused. But above all, they are also easier to use. " They are pleasant to handle, and require simple construction techniques that are much more accessible and understandable for everyone. And they're just as forgiving of the mistakes you can make when using them," she smiles.

Through her work in this field and her teaching, Sophie Trachte hopes that she and her colleagues will be able to influence current renovation policy. reusing buildings by transforming them is really part of our culture," she says. But the current socio-economic situation is such that if we force a large number of citizens to renovate their buildings, they will turn to cheap solutions that will only shift the problem 20 to 30 years from now in terms of waste! "

For the architect, this is partly due to the unit used. we count energy consumption in kilowatt-hours per square metre, when in reality we should be looking at people's overall energy balance (heating, transport, consumption)," she muses.For example, you could be living in the countryside in a house with a passive energy standard, and still lose all the energy benefits of that house through daily car journeys to work or the office. Conversely, you could renovate an old urban building to make it moderately efficient, but choose to use public transport and consume locally. I really think that such a calculation would make people aware of the energy impact of their behavior, but also give them the choice to decide what they want. "

Broadening our thinking

Faced with the challenge ahead, Sophie Trachte has decided not to sink into anxiety or fatalism. we're living in a very special transitional momentum, which motivates and thrills me," she enthuses. And I say to myself, while we're at it, let's dare the impossible! Let's keep moving forward, and find the courage to get moving in the face of this world and these major challenges for which we need to find solutions. We mustn't innovate at any price. We have to do it while moving towards greater sobriety and social equity, while working for our ecosystem and for all the world's citizens "

A voluntary approach that she also seeks to pass on to her students. i'm so ashamed of the world we're leaving them, and the profound changes it's undergoing," she muses. I'm trying to teach them that they're going to have to find the courage to limit themselves, and that the only way to do so will be together, by pooling intelligence and skills. For me, it's the role of the university to encourage multidisciplinary research that broadens thinking, making it more complex and fairer. Because I'm convinced that we'll find solutions by changing the way of thinking that has created the current problems. "


ULiège in transition
The University of Liège is committed to the transition to a more sustainable world!

As a place where scientific knowledge is produced and transmitted, the University has a major role to play. It must not only support society's transition, but also consider its own transformation. The new rectoral team has placed the environmental and social transition at the heart of its program and made it a transversal and structuring element of its institutional strategic plan.




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ODD 3 : Bonne santé et bien-être
Donner aux individus les moyens de vivre une vie saine et promouvoir le bien-être à tous les âges Le troisième objectif vise à assurer la santé et le bien-être de tous, en améliorant la santé procréative, maternelle et infantile, en réduisant les principales maladies transmissibles, non transmissibles, environnementales et mentales.
ODD 11 : Villes et communautés durables
Faire en sorte que les villes et les établissements humains soient ouverts à tous, sûrs, résilients et durables Le onzième objectif vise à réhabiliter et à planifier les villes, ou tout autre établissement humain, de manière à ce qu’elles puissent offrir à tous des opportunités d’emploi, un accès aux services de base, à l’énergie, au logement, au transport, espaces publics verts et autres, tout en améliorant l’utilisation des ressources et réduisant leurs impacts environnementaux.

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