Introduction

The construction industry is one of the largest consumers of energy and raw materials globally. Within the EU, it contributes to nearly 40% of emissions and accounts for almost a third of all waste generated. Only around 40% of construction waste undergoes recycling or reuse during building demolition. Typically, recycled construction materials find application in secondary construction rather than in new building projects. Embracing a circular approach within the building sector holds significant promise for delivering environmental, social, and economic advantages. For this, circular construction necessitates a re-evaluation of building design practices, focusing on reducing embedded carbon, utilising recycled or bio-based materials, designing for material and component reusability, and prolonging building lifespans through better maintenance. 

How can circular construction be defined? Circular construction entails the creation, utilisation, and repurposing of buildings, construction elements, products, materials, spaces, and infrastructure, all while minimising the depletion of natural resources, environmental pollution, and negative impacts on ecosystems. Specifically, regarding buildings, a circular structure maximises resource utilisation and minimises waste across its entire lifespan. If a new construction is built, it should be designed for longevity, adaptability, and disassembly. New buildings should be built efficiently and with recycled, renewable, and non-polluting materials. According to the “Circular Buildings and Infrastructure” report by the European Circular Economy Stakeholder Platform (ECESP), the main aspects of circular construction include:

• Design for deconstruction

• Material reuse and recycling

• Resource efficiency (e.g. by choosing efficient design that minimise material waste, adopting prefabrication techniques, implementing lean construction practices, etc.)

• Circular business models

• Digitalisation and data management that can support better tracking and management of materials and support decision-making.

Recognising the construction sector as one of the eight sectors with the highest circularity potential, the EU Circular Economy Action Plan delineates a series of actions to be undertaken. Additionally, the Waste Framework Directive prioritises construction and demolition waste as a priority. Local and regional authorities wield the potential to steer transformation within the construction sector. In fact, given their management of an extensive array of public buildings and considerable purchasing power, they can significantly influence market conditions.

The importance of the net-zero agenda is widely recognised, however there remains considerable discussion regarding its integration with improvements to the built environment. Strategies such as reducing energy consumption, optimising designs, employing low-carbon materials, and embracing digital technologies all contribute to this goal. Nonetheless, it is imperative to adopt circular economy principles, wherein buildings are conceived to be assembled, utilised, disassembled, and repurposed as necessary. This approach not only aligns with the net-zero agenda but also prioritises waste reduction in building design.

The European Union has committed to achieving climate neutrality by 2050, aiming for an economy with net-zero greenhouse gas emissions. Given that Europe's buildings account for 40% of total energy consumption and 36% of CO2 emissions, significant efforts have been directed towards enhancing the energy efficiency of buildings during their operational phase. However, it is essential to also consider CO2 emissions generated throughout other stages of the building's value chain to achieve rapid emissions reductions. Addressing embodied emissions presents a challenge for the EU in decarbonising the built environment, as they are currently categorised within the industrial and waste sectors rather than the building sector. These embodied emissions are estimated to comprise between 10% and 20% of construction-related CO2 emissions in the EU, and in certain European countries, this figure could be as high as 50%. To effectively decarbonise the built environment, circular economy and circular construction offers a pathway to ensure the efficient use of resources and to mitigate embodied emissions generated across various stages of a building's life cycle.

European policy context in circular economy

Circularity in construction is regulated through several directives and frameworks within the EU. Here are the most relevant:

• Circular Economy Action Plan: it paves the way for a cleaner and more competitive Europe, and it is one of the main blocks of the EU Green Deal. The plan supports the EU´s transition towards a circular economy which is necessary to achieve climate neutrality targets. It aims for a sustainable built environment characterised by building material efficiency and reduced climate impact through circularity principles in the whole life cycle of buildings. It is expected that the launch of a new comprehensive Strategy for a Sustainable Built Environment in 2024 should guarantee coherence across policy areas, such as construction and demolition waste, climate, energy efficiency, accessibility or digitalisation.

• Waste Framework Directive (WFD): this sets the basis for waste management, including the definition of waste, recycling, and recovery. According to this Directive, Member States were obliged to reuse, recycle and recover 70% of non-hazardous construction and demolition waste by 2020, and minimise waste generation.

• Energy Performance of Buildings Directive (EPBD) and Energy Efficiency Directive (EED): they both aim to achieve a fully decarbonised building stock by 2050. In particular, the revised EPBD will boost the Renovation Wave by setting up national building passport schemes to guide building owners during the renovation to reach zero-emission buildings. The revised directive also introduces a disclosure of whole life cycle emissions for buildings (“A requirement to calculate the life-cycle global warming potential of new buildings constitutes a firs step towards increased consideration of the whole life-cycle performance of buildings and a circular economy”).

• Level(s) is the European framework for sustainable buildings, providing a common language to assess their performance. It also offers an extensive tested system for measuring and supporting improvements from design to end of life of residential buildings and offices.

• Taxonomy regulation: it defines economic activities aligned with the EU net-zero trajectory by 2050 and broader environmental goals.

• New Construction Products Regulation will enter into force in 2024 and will provide a common technical language to assess the performance of construction products. Circularity aspects are integrated to ensure that architects, engineers and construction companies can take informed decisions.
   

Financial instruments and initiatives for implementing circular economy

There are also various financial instruments and initiatives which support Member States in implementing circular economy and circular construction principles. Some examples are:

• The EU is providing several funding programmes to support the transition towards a circular economy, such as through the Horizon Europe and LIFE programme. The former has set a budget of EUR 95.5 billion under two Missions: ´Climate Neutral and Smart Cities´ and ´Adaptation to Climate Change´. The latter has allocated a budget of EUR 1,35 billion to the ´Circular Economy and Quality of Life´ subprogramme for the period 2021-2027.

• The European Investment Bank (EIB) provides finance and advice for circular projects through the InvestEU Advisory Hub

• Sustainability financial package includes a delegated act establishing technical screening criteria to qualify economic activities as contributing to the transition to a circular economy, among other aspects.

• The private sector also has the interest of supporting the transition to circularity principles by redirecting capital flows towards sustainable investments and mobilising available public funding sources.

• Concerning initiatives, the European Forum of Technical and Vocational Training (EfVET) has launched a cooperation project of four VET schools in the topic of circular buildings. These schools are Deltion College (NL), Salpaus Further Education Regional Consortium (FI), Hohere Technische Bundeslehranstalt Zelftweg (A) and Fondazione ITS Energia Ambiente ed Edilizia Sostenibile (I). The aim is to exchange information about circular building developments in those countries and the EU, while also developing learning materials and international student activities regarding circular building.

Circular economy organisations

• Circular Building Coalition aims to accelerate the transition to a circular built environment in Europe. It involves stakeholders of the built environment to overcome barriers and embrace sustainable practices.

• European Environmental Bureau is the largest network of environmental citizens´ organisations in Europe. Among several areas covered, it supports the development of circular economy principles.

• European Circular Construction Alliance (ECCA) is an EU meta-cluster supporting clusters and business network organisations, SMEs and members collaborating for innovation, market uptake, and marketing competitive products, services and technologies in the field of circular construction.

EU-funded projects related to circular principles in construction

Horizon Europe programme

• EASI ZERo aims to use bio-sourced and recycled materials to enhance the thermal performance of new and existing buildings’ envelopes by 20%. The diverse materials include grown mycelium, wood fibres, low carbon foam, recycled raw material. The project thus addresses the growing need to cut the environmental impact of EU buildings.
  

• GreeNest aims for a transformative approach to sustainable and low-carbon building practices which integrate CO2-neutral building materials, such as reused, recycled and locally sourced biogenic elements with renewable energy sources. This ecosystem requires fewer materials and adopts energy efficient circular practices.
  

• RECONSTRUCT aims to replace carbon-intensive materials with a blend of construction and demolition waste, avoiding traditional Portland cement. It also aims to create modular elements for easy disassembly, encouraging reuse and recycling.
  

• DRASTIC aims to implement whole-life cycle GHG emission reduction in new construction and retrofit by demonstrating affordable and innovative circular solutions in five geographical areas, covering different building layers, raw materials, building typologies, circular strategies, and local drivers.
  

• INBUILT aims to advance sustainable building practices and reduce the carbon footprint of buildings through their entire life cycle in Europe. To achieve so, it involves the development and demonstration of ten innovative products and systems, such as recycled concrete and recycled concrete blocks, bio-based prefabricated curtain walls, bio-based recycled insulation sheet panels/infill and second life photovoltaic panels, etc.
  

• CIRC-BOOST aims to foster circularity in buildings and the construction sector through the development and deployment of both digital and technical solutions in building urban material databanks, digital twins, as well as demolition, decontamination and recycling and reuse of waste materials.
  

• circEUlar aims to develop circular pathways for the EU low-carbon transition. It will develop new modelling approaches for analysing circularity and understand the transformation of society towards a net-zero emission circular economy. It will contribute to the objectives of the EU by assessing the feasibility and new technologies, processes and products combining them to the new business models for more sustainable and circular buildings.
  

H2020 programme

• BusGoCircular aimed to address and overcome the challenges of demand for green energy skilled workforce by developing and implementing a circular construction skills qualification framework with a focus on multifunctional green roofs, facades, and interior elements.
  

• CIRCuIT supported the creation of regenerative cities by implementing sustainable and circular construction practices. Through a variety of means, it showcased how circular construction approaches could be scaled and replicated across Europe.
  

• HOUSEFUL introduced solutions to become more resource efficient throughout the lifecycle of the building, taking into account an integrated circular approach. The concept has been demonstrated in four demo-sites adapting the approach to different scenarios, including social housing buildings.
  

• ICEBERG aimed to create innovative tools and technologies to advance the industry´s uptake of circular economy. It developed an upgraded building information modelling-aided smart demolition tool, a novel digital end-of-life building materials (EBM) traceability platform and a radio frequency and quick response-based identification system.
  

• DRIVE 0 aimed to speed up the deep and circular processes by improving a customer centred circular renovation process. The purpose was to make the approach of circular renovation more attractive for consumers and investors, environmentally friendly and cost effective.
  

• ARV aims to demonstrate and validate attractive, resilient and affordable solutions that will speed up deep energy renovations and deployment of energy and climate measures in the construction industry. It will provide guidelines and policy frameworks for future energy-efficient, circular, and digital solutions.
  

LIFE programme

• LIFE22-CET-TOP CLeveR aims to empower construction professionals and workers with the skills needed to face the challenges of the whole life carbon and circular approach along a building life cycle. The project also supports the implementation of Level(s) framework. It will also develop and test VET programmes and activities for white and blue collars.
  

Conclusion

As one of the largest contributors to emissions and waste generation, the construction industry holds immense potential for mitigating environmental impact while simultaneously fostering economic growth and social well-being. Embracing circularity means rethinking every aspect of the building process, from design to end-of-life considerations. It involves maximising resource efficiency, promoting material reuse and recycling, adopting circular business models, and leveraging digitalisation for improved tracking and decision-making. By prioritising circular construction, Europe can not only meet its climate targets, but also pave the way for a greener and more sustainable future.

Do you want to know more about circularity in buildings? Check our Expert Talk with Michiel Ritzen!