Executive summary

Construction and demolition waste (CDW) accounts for more than a third of all waste generated in the EU. The EU Waste Framework Directive (2008/98/EC) states that by 2020, the preparing for re-use, recycling and other material recovery is to be increased to a minimum of 70 % by weight for CDW. Studies show that the Nordic countries are not yet reaching this target.

At the same time, one of the three strategic priorities in the vision of the Nordic Councils of ministers “A green Nordic region” is promoting green transition and working towards carbon neutrality and a sustainable circular and bio-based economy. The main goal of this study is to support the circular economy domain while also contributing to the achievement of the goal of “Resource-efficient and non-toxic cycles”. To support the goal, the study aimed to identify and present relevant techniques and facilities regarding reuse and recycling of construction and demolition waste in the Nordic market. It also included an inventory of the construction and demolition waste streams that currently are difficult to reuse or recover and finding ways forward to improve the situation.

EU legislation and targets serve as the foundation for how waste should be handled in the respective countries. Additionally, there are country-specific legislations applied nationally concerning CDW, with some countries, such as Denmark and Finland, having more extensive and stricter legislation than what the EU regulations entail.

The primary methods for treating CDW in the Nordics involve low-value recovery, such as energy recovery and backfilling. Some of the key challenges associated with recycling and reusing CDW include treatment and transportation costs, as well as the lack of on-site sorting. In Denmark, which boasts the highest recycling rates in the Nordics, recycling is generally less expensive than other treatments, largely owing to short distances and high landfill costs. Conversely, the widespread availability of waste incineration capacity and inexpensive raw materials, such as wood and aggregates, across most of the Nordics hinders the growth of recycling.

Both on-site sorting and pre-demolition audits were acknowledged as important factors for attaining high recycling rates and obtaining high-quality materials from CDW recycling. On-site sorting for both construction and demolition waste aids in producing high-quality materials for recycling. The pre-demolition audit helps identify and separate materials containing harmful substances used in previous decades, serving as an essential tool to identify reusable construction elements.

CDW fractions such as gypsum waste, mineral wool waste and reject from mechanical treatment of mixed CDW have been considered problematic to recycle in certain Nordic countries. These waste fractions have higher recycling rates in other countries where good treatment examples and demolition practices could be identified in this study. For example, in Denmark the reject from mechanical sorting of CDW is not considered as an issue, as CDW is separated more efficiently on-site.

The lack of detailed statistical information has been identified as an obstacle for conducting thorough analyses on which waste material streams are not currently recycled. For instance, numerous waste fractions are commonly consolidated under a single waste category (e.g., mineral waste). “You can’t manage what you can’t measure” applies here and to better identify and encourage the recyclability and reuse of specific material categories, significant potential lies in improving the sorting, documentation, and reporting of CDW. Among the Nordics, Denmark currently possesses the most comprehensive CDW statistics available. Denmark also reports significantly more CDW per capita, which could be due to, e.g., more detailed and comprehensive data, higher rate of stone buildings that weigh more than wood buildings, and that due to short distances, more waste is recorded instead of direct backfilling or recycling of mineral materials on-site. Also, the statistics can vary a lot from year to year.

Table 1: Summary of the main CDW treatment methods for different fractions in Nordics.

	Reuse	Recycling	Material recovery	Energy recovery	Disposal
Mineral (concrete, tiles, etc.)			DA, FI, IS, NO, SE
Metal		DA, FI, IS, NO, SE
Glass		DA, FI, NO, SE	IS
Wood		DA		FI, IS, NO, SE
Plastic				DA, FI, IS, NO, SE
Plaster		DA, NO, SE			FI, IS
Mineral insulation wool		DA			FI, IS, NO, SE
Reject from mechanical CDW separation					FI, IS, NO

In the study, initiatives, and methods of CDW recycling and reuse in other European countries with high recycling rates are briefly described. Case examples highlight various successful business opportunities and techniques recycling practices and reuse of materials, as well as concludes with a policy overview of high-performing countries, such as reuse of bricks or other materials using techniques adapted to local market, sorting using AI and examples of recycling materials that are difficult to recycle in other countries. High-performing countries share common features such as effective legislation promoting a circular economy, the presence of suitable businesses and facilities, and innovative projects often in public-private partnerships.

The drivers influencing CDW recycling and reuse can be categorized into legislative and political, economic, technical, social, and cultural factors. This study emphasizes recommendations that underscore the significance of unified approaches within the Nordic countries and the EU. These recommendations include implementing end-of-waste regulations, extended producer responsibility, climate and resource targets, providing waste tax incentives, creating market value, establishing investment funds, improving on-site sorting, and developing standardized guidelines.

This study concludes that:

The barriers for increased reuse and recycling of CDW are not technical. Techniques for recycling and reuse are available, but the upscaling of these are met with different legislative, economic and social barriers in all countries.
The biggest barriers are economical and for some regions especially, long distances and small volumes. Also, attitudes and norms play a role.
There is a lack of economic incentives both to recycle CDW and to use recycled materials.
Data gathering and reporting is difficult.
Better on-site sorting would enable more high-quality reuse and recycling.
Pre-demolition audits are key in sorting out reusable and hazardous materials.
There are regional differences in treatment and materials difficult to recycle in some countries, such as gypsum demolition waste, mineral wool demolition waste and reject from mechanical treatment of mixed CDW have higher recycling rates in other countries.
There are many good innovations and many start-ups and projects, but as upscaling into a main business model is challenging, these examples are harder to find.
Waste prevention by reusing, but especially by preventing demolition, should be the first step.

There is a need to establish unified approaches to enhance cooperation and opportunities within the Nordics and the EU, particularly concerning data development and policies.

An important step that remains underutilized in the prevention of CDW is promoting reuse, as well as implementing measures to prevent buildings from being demolished, for example by renovating and refurbishing. For new constructions, incorporating design for disassembly, adaptability, and material passports will aid in waste prevention and promote reuse and recycling in the future.