Circular Economy is the future for the construction industry, but it remains far from mainstream. Six finalists in the Circular Construction Challenge – Rethink Waste, demonstrate what the future solutions for circular construction look like.

This article is written in cooperation with Realdania


Fungus spores cultivated in waste that can be transformed into insulation, baffle plates, or construction materials. EPS waste from construction and packaging transformed into brand new building materials using robot technology.

These are two of the six innovative solutions which made it to the final of the so-called Circular Construction Challenge – Rethink Waste. The six finalists were announced at the annual Building Green Conference held in Copenhagen at the end of October – see textbox.

The Challenge was initiated by the Danish philanthropic association Realdania, with the ambition of identifying, developing, and scaling new solutions to the massive waste and resource challenges threatening the construction sector today. Read more in the end of the article.

“The world calls for new solutions so that the enormous amount of new construction projects that need to be carried out over the coming decades will be built based on new circular methods. We need to create new solutions that enables us to make use of the large flows of waste coming from the construction sector, so we can reduce waste and limit the resource pressure of new construction projects. It requires new thinking and innovation, and that is what we try to promote with this Challenge,” says Simon Kofod-Svendsen, Head of Projects for Realdania and responsible for the Circular Construction Challenge.

Their ambition is that the six finalists will become inspiring business solutions that showcase how we can build based on circular principles. The next step in the Challenge, selecting the three winners in February 2019 is thus for the six finalists to develop a business case, and put together an international team that can help develop and scale the solution for a global market. See textbox.

The six finalists have the potential to be internationally scalable and innovative new business solutions. This is the conclusion from Chris Murphy. He is a representative of the International Solid Waste Association (ISWA) that works to promote and develop sustainable waste management systems with member companies and waste associations all over the world. He is also one of the nine experts in selection committee that chose the six finalists.

“There is no silver bullet when it comes to making the construction sector more circular, but the six finalists have developed very qualified examples of how future circular solutions could look and of how to think circular rather than linear in the construction sector – some of which clearly have the possibility to be scaled globally,” says Chris Murphy.


Textbox: The six finalists and their ideas
Golder Associates:
Circular Alternative – reused timber in large-scale retail sale is a system where timber from temporary constructions at construction sites is collected and sold for reuse via the building market STARK.
Vandkunsten:
RePanel is wall lining made of construction waste from renovations and demolition sites. The final product is a flexible, modular system with highly profiled identities – patterns, materials, and shapes – which are both decorative and assist in insulation.
Søren Jensen Consulting Engineers:
From Waste To Biomaterial is a new sustainable building material – like baffle plates and insulation – produced by growing fungus/mycelium spores in waste flows, which can replace existing building materials with negative environmental impacts.
RGS Nordic:
Urban Mining Of Masonry is reused brickwork or masonry and concrete transformed into a robust material to be used to construct walls.
Odico Formwork Robotics:
Digichalk is a building module that combines Styrofoam waste with chalkstone and cement through innovative robot technology. The material has the same insulation effect as Styrofoam, the same density as concrete and the look of chalkstone.
Krydsrum Arkitekter:
Reskur is a building system for sheds (e.g. for bikes, waste bins or office supplies) made from recycled timber and tiles from roof material waste.

We need circular thinking

The point of departure of the Circular Construction Challenge is a large and growing pressure on the construction sector to provide sustainable solutions. At a global level, the construction sector is responsible for 40% of the total material consumption. Furthermore, the sector is one of the world’s largest producers of waste: 1.3 billion tons of waste is produced globally every year and half of this comes from the construction sector. In addition, according to the World Economic Forum less than a third of construction waste is reused or recycled.

Looking towards 2030 and 2050, these numbers will not decrease. On the contrary, projections indicate that the world population will grow rapidly and that cities will experience accelerating rates of urbanization. Consequently, we will see an increasing global demand for new housing, roads and other facilities. In a business as usual scenario, this will increase resource consumption from the sector markedly.

Therefore, the construction sector is confronted by a need for new solutions to steer the sector onto a more sustainable path. And this is where the transition to circular construction becomes a decisive lever to reduce the negative environmental impacts of the sector.

“For years we have had a linear approach to waste in the construction sector. That is not a sustainable approach anymore. Today, we can see the value of second use and waste as a value,” Chris Murphy says.

Growing political focus

Promoting circular thinking within the construction sector is drawing increased attention among policy makers. In 2015, the EU published a plan of action for a circular economy, and passed on legislation earlier this year that will promote circular waste management.

On a national level, circular thinking in the construction sector is also gaining grounds – for instance in Denmark, where the government published their ‘Strategy for Circular Economy’ in September 2018. In this strategy a more circular construction sector was highlighted as a cornerstone. Among other things, the Danish government announced that engineering and construction companies who develop and apply circular methods and tools in the future will receive competitive advantages in public tenders: “From now on, when the [Danish] State initiates new building projects, we will favor the entrepreneurs who reuse their materials,” the Minister of State for Trade and Industry, Rasmus Jarlov said at the presentation of the new strategy.

In addition, the adoption of UN’s 17 Sustainable Development Goals and the Paris Agreement obliges the international community as a whole to seek more sustainable production and to use less resources – an obligation that, seen in the light of the current resource consumption, issues new demands on the construction sector.

Circular construction = growth

It is not just from an environmental or political perspective that the transition towards circular construction makes good sense. In a world where resources are strained and the demand for sustainable solutions are rapidly growing, there is an enormous economic growth potential embedded in circular thinking.

Looking at the Danish construction sector as an example, the business potential of circular thinking is striking. The Ellen MacArthur Foundation, recognized as the authority on circular economies, indicated that through a transition to more circular thinking, Denmark could enjoy US$ 7 billion in profits, and see national exports increase 4-5% by 2035. The Danish construction sector is one of the sectors with the largest opportunity to embrace circularity, with potential growth of US$ 630-840 million in 2035.

Andreas Castberg, business development leader at the engineering company Søren Jensen, is well aware of the strong business case of circular construction. The company is one of the six finalists of the ‘Waste to Biomaterial’ initiative, aiming to develop new building materials through fungus spores cultivated in waste.

“We see a large potential in providing solutions to the market that can make the construction sector more sustainable. We have an ambition to be a part of the next generation of sustainable building – and here, the circular thinking is very important,” says Andreas Castberg.

Circular thinking is spreading, but still far away from being mainstream

Circular economies, circular construction and circular thinking are not completely unknown to the construction sector. The diversity of ideas amongst the numerous applicants in the Circular Construction Challenge is a shining example of this. Another is the growing focus on certifications for sustainable construction which for the most part treat circular thinking as the centrepiece. One example is the DGNB certification, which includes life cycle assessments of building materials and demands evidence of the use of circular principles.

Looking again at the construction sector in Denmark, a palette of large and international Danish companies have developed and scaled recycled building materials and engaged in circular construction projects in recent years. One example is the Danish construction project Circle House’, a social housing project to build 60 general housing units. The overall aim of the project is to become the world’s first building project where more than 90 percent of the building materials can be recycled without losing significant value. The Danish architecture firm GXN and the construction company MT Højgaard are collaborating to bring the project to fruition. The project is to be finished in 2020 and will serve as a prototype through which we can gain further knowledge about circular construction practices.

But despite growing interest, new certifications and demonstration projects, much progress is to be made before circular thinking becomes the mainstream approach. A report by the Danish Construction Association thus shows that only four percent of all ongoing construction projects are sustainable. Furthermore, a recent report on circular economy from the Danish Technological Institute shows that only every fifth company expects more than half of their building materials to be recycled within the next 4-5 years.

It is this mainstreaming of circular thinking that Realdania wants to accelerate with the challenge:

“With this challenge we hope to show that it is in fact possible to have a circular mindset, and we hope to come up with some scalable solutions that are ready to be used in the sector,” says Simon Kofod-Svendsen from Realdania.

Next move: Partnerships and commercialization

One of the most important factors in driving circular construction is partnerships across the entire value chain. Circular construction requires that all stakeholders, from the first draft, to construction, to the demolition, are cooperating to make best use of resources and avoid waste of materials. Therefore, the capacity to think and act across the value chain is one of the most important factors that the six finalists are selected by. Towards the final selection of the three winning solutions in February 2019, a main focus of the six finalists will thus be – with inspiration from the recommendations of the selection committee – to establish a strong, interdisciplinary team of relevant actors who can strengthen the possibilities of development and implementation of the idea.

“The solutions come from the entire value chain and are at very different stages of their product development. We will be working with the six finalists to develop their business focus and to build up a team that can turn the initial idea into a solid business case,” Chris Murphy says.

The statement is supported by another member of the selection committee – the Director Cooperative and Corporate Sustainability of the Dutch pension fund, PPMG, Frido Kraanen:

“Going forward, the challenge for the finalists will be to develop a multidisciplinar outline that also includes the commercial part. And then the focus in the next phase should be (…) to shift the focus from a material to design of a commercial solution,” he says. According to Simon Kofod-Svendsen, the capability to think and act across the value chain and put together the right team is a decisive factor when it comes to finding the three winners: “Partnerships are crucial for bringing innovations from being just ideas to real scalable business solution. So now we begin the next exciting phase, where the six finalists need to form teams so that they can gain the necessary capabilities. The strongest teams are the ones that are able to set a team with the right technical resources, and partner with actors who can supply the ‘waste’ to their solution, and who are interested in using the solution afterwards”.


Circular Construction Challenge – Rethink Waste
In August 2018, Realdania and Danish Design Centre introduced the innovation challenge Circular Construction Challenge – Rethink Waste, bringing into focus new solutions to minimize construction waste.
The challenge was launched with a call for solutions, with final closing date on the 8th of October 2018. Thirty-nine applications were received.
After the deadline, the group of applications was reduced to 10 who had the opportunity to pitch their ideas on the 23rd of October to a selection committee of nive experts – among these Chris Murphy from the global waste association ISWA, Frido Kraanen, director of the Dutch pension fund PFFM, and Christian Bason, director of the Danish Design Centre.
Against this background, six finalists were selected, and announced at the Building Green conference in Copenhagen Until the 3rd of December deadline, it is possible to apply to join in as a team member for one of the ideas. After that, the finalists choose their teams, develop partnerships and give a presentation pitching their idea, illuminating their business case, and showcasing how they would use the prize money of US$ 150,000 USD to bring this idea to life.
Three winners will be selected in February 2019, who will then have six months with their teams and the prize money to develop their first prototype. When the prototype is finished in the Summer, they will receive support with international exposure and market access.Read more about the challenge, the six finalists and how to apply to join one of the six teams here www.circularconstructionchallenge.org