for reuse
in construction
Manifesto
The Swiss construction sector generates about 74 million tons of waste annually, of which about 17 million tons (19%) is construction material [1]. Of the construction waste generated annually, about 75% is recycled, 20% landfilled, 4% incinerated and only a fraction reused [2].
In order to build sustainably and in a climate-friendly way, we need to focus on the circular economy and view construction as a cycle. Demolition projects play an important role in this, as many of these buildings are veritable treasure troves of reusable elements: Windows, supporting structures, facade cladding, etc. However, most demolition projects are not suitable for recycling.
Cirkla unites the actors of the reuse scene in Switzerland on the basis of this statement and the following values:
1. we must drastically reduce CO2 emissions, limit resource extraction, and reduce our waste production associated with construction projects.
Detailed position
In Switzerland, the construction industry consumes 70 million tons of material every year[3]. Globally, the industry is responsible for 37% of greenhouse gas emissions, with energy emissions from construction - mainly from the production of construction materials for buildings - accounting for 10% of this total[4].
Reuse is one of the most effective tools for reducing greenhouse gas emissions, conserving resources and limiting waste in the construction sector.
Reuse has several environmental benefits:
- It makes it possible to save the gray energy required for the manufacture, transport and use of the existing construction elements.
- It makes it possible to limit the production of greenhouse gases caused by the creation of new materials.
- Finally, it limits the extraction of valuable (and sometimes scarce) resources needed to produce these new materials.
2. recycling our waste will not be enough. In a circular economy, we must implement strategies to reuse materials and building components before they are sent to landfills.
Detailed position
In Switzerland, at a deconstruction site, except at the special request of the client, materials are only separated destructively, sorted, usually on site, and sent for recycling in accordance with the "Ordinance on the Limitation and Disposal of Waste" (Federal Council 2020).
This must change.
Reuse follows the principles of the circular economy, which is defined as a cyclical economic concept that seeks to do without waste.
In the specific field of construction, the different ways of limiting and treating waste are hierarchically ordered according to the logic of the short cycle. They come into play at various decision-making stages of the construction process and are listed here in a preferred order:
- Abstain from or reduce intervention.
- Prefer the repair of construction elements to replacement.
- Prioritize the rehabilitation or conversion of existing buildings over demolition and replacement with new construction.
- Reuse of components is preferable to recycling.
- Recycling instead of landfill.
To reduce the amount of construction and demolition waste, we must ensure that each non-renewable component of the building retains its inherent qualities for as long as possible to allow for the widest range of potential uses.
Reuse is undoubtedly the most energy-efficient process for transforming a product. The recycling of materials or components is extremely costly and these costs, which are not made visible by the major manufacturers, are rarely recorded. Products are recycled, but how often and at what cost?!
3. we cannot ignore what is already there. By reusing, we enhance existing buildings, as a whole and as parts, as a whole or as individual parts.
Detailed position
To influence the future, you must look at what is here and now. Enhancing what already is recognizes the value of our built heritage and the history of our cities and landscapes.
We should consider the existing building stock as an inalienable starting point. We should prohibit ourselves from any demolition without first considering the value of the building fabric as a reusable set of elements. This is a paradigm shift in terms of our relationship with the building fabric, which is becoming the available bank of materials now and over the next decade. We need to find solutions that are rooted in the reality of dealing with buildings and materials with unknown properties and without detailed data. The solution will not only lie in complex digital systems that are still being developed, but also and above all in simple and concrete principles that are immediately applicable and accessible to everyone.
This work is urgently needed, as demolition and new construction are releasing large amounts of greenhouse gases at a time when scientists are calling on us to rapidly decarbonize our societies.
For decades, the focus has been on energy efficiency, but in practice, the savings in operating energy are quickly surpassed by the high gray energy expenditures that demolition/new construction entails. The inclusion of gray energy in a project's energy footprint needs to be quickly mainstreamed so that we collectively become aware of its importance and the levers that allow us to reduce it.
Reuse is an important tool to achieve this.
4. we take care to build with the awareness of future reuse.
Detailed position
Is every production an evolving waste?
The only source of energy outside the earth is the sun. The tree, of course, is the only living thing that produces an "extra being," so to speak, from the sun. All living species, as long as they remain in balance with the sun, produce only waste that returns to the cycle of nature. The human species is the only species on Earth that produces waste that cannot return to the state of nature. The question arises whether every production is not an excess, a potential waste.
The concept of circular economy proposes to eliminate the concept of waste: Everything goes back into the cycle, to infinity.
For the construction industry, this means planning ahead. Whether it's reusing building elements or producing new ones, it means building in such a way that a building can be easily disassembled, but also designing flexible buildings with a longer lifespan, sharing information about the elements used (what they're made of, what their properties are), and storing and managing that information to facilitate the reuse of those materials and building elements in the future. This also means predicting what will happen to these materials when they no longer serve their original purpose.
Is this possible? We are convinced of this and are sowing the seeds for this future today.
5. we upgrade the construction professions, craftsmanship and local work.
Detailed position
To work with reused materials means to valorize the know-how and inventiveness of the craftsmen: the building trades are more and more caught by the massive industrialization of the building elements, which impoverishes the knowledge of these trades. The reuse of building elements leads to a feedback of knowledge and reflection on solutions for connections, assembly and use.
One of the consequences of the systematic industrialization of building elements is the standardization of the built landscape. The reuse of building materials leads to a new inventiveness in building, from design to execution, at every stage of the process.
Reuse shifts the amount of energy needed to mass produce a building element in a factory into the hands and minds of artisans.
Reuse creates jobs, local jobs and appreciative jobs.
6. we recognize the importance of a variety of actors and strategies, whether they are industrial processes, historical upgrades, or artistic potential.
Detailed position
The motivations for reusing building materials are diverse, leading to a wide range of responses to the question of how to integrate the world of construction into the circular economy. Reuse in architecture is meaningful on several levels: social, constructive, historical. Some propose an economic vision of reuse, while others see a patrimonial, artistic, or even philosophical dimension to it.
Artists who create a vision, a temple of ecology, a typology of surprising elements. They take the time to look for the parts for their vision and find the craftsmen who bring them to life.
Architects who plan how to integrate reused elements into a project, who believe that it is better to renovate than to demolish. They need to convince their colleagues and clients and figure out how to put this vision into practice.
Builders working on large projects, portfolios of office and residential buildings, taking a fresh perspective on their building stock and seeing each demolition as a treasure trove of materials and new projects as an opportunity to reuse them.
Policymakers who are willing to test reuse in public projects, who are looking for information, who want to know how to do it, and who are asking for support.
Contractors and craftsmen who are changing the way they work on their construction sites. They are rethinking their ways of working in order to process reused materials and are introducing innovations so that they can be reused in the distant future.
Collectors and resellers of building materials and elements, some of whom have been doing this for a long time, who know how to break down elements, analyze what can be sold, and upgrade what would be waste for others.
Those who work to preserve our history and cultural heritage by preserving, protecting and restoring listed buildings. They also participate in the project, because the first step is to keep a building in use as long as possible.
It is this diversity of approaches that gives re-use the momentum and visibility it has today.
Cirkla seeks to represent all these actors.
7. we need to change the architectural and construction process so that reuse can be integrated into the thinking and practice of our professions.
Detailed position
Incorporate reuse into the construction process ...
... is (to leave yourself) room for decisions that have to be made later ..;
... is to leave bags open for the long duration of the construction site;
... is to extend the drawing into the materiality of the project;
... is to accept that not everything is fixed from the beginning;
... it's a way of keeping the idea of the project alive throughout the construction period;
It is also an exercise in humility!
This swaying of the demiurgic character of architecture also allows a horizontalization of the "usual" hierarchies on a building site, so that space is truly made for a collective. This practice forces the architect to reconsider him/herself, to step out of the refuge of drawing and planning in order to enter into a collective action of all. He/she must redefine the scope of his/her action and competences.
You also have to ask the question of time: Reuse requires taking time, time to collect, time to think creatively, time to assemble. Three times as much time for three times as much awareness for living.
Reuse also makes us aware that we cross generations. Through the "anachronistic" presence of a returned, reused element, we become aware that there was a before us and that therefore there will be a after us.
It is also a matter of adapting existing processes, rules and standards to facilitate their implementation so that it becomes normalized. We need to introduce systematic inventories of the building materials and elements that make up the existing building fabric in all cities and throughout the country, so that the procurement of reusable materials remains a treasure hunt but is no longer an uncertain and endless quest.
Reuse should no longer be the preserve of the unconventional and the brave (although they are leading the way). It transforms the zero carbon goal into a creative process and social cohesion through the construction of places inhabited by humanity, in an awareness and with a strong imprint of respect for the earth on which we live.