Tampere University

May 27, 2026

Paul Jonker-Hoffrén, Tampere University

Introduction to the report: Guide to national implementation differences of norms applicable to reuse. The full report is available here.

Transitioning the construction sector from a linear “take-make-waste” model to a circular one is a monumental task. The ReCreate project is researching how to reuse precast concrete elements—originally never meant for disassembly—across four European countries. However, as the project has progressed, actors on the ground have found that the biggest barriers aren’t always technical; they are often found in the fine print of national regulations.

“Guide to national implementation differences of norms applicable to reuse” looks at the practical aspects of translating existing regulation for reuse of reclaimed precast concrete elements. It is based on the experiences gained from interactions with regulations and policies in ReCreate’s pilots.

Finland: reclaimed precast concrete elements are not waste

In Finland, the ReCreate pilot faced a difficult question in conjunction with the temporary storage of the reclaimed elements: Are deconstructed concrete elements “products” or are they “waste”? If labelled as waste, the elements would be subject to expensive, time-consuming administrative processes like the “End-of-Waste” (EoW) process. In addition, such labelling also would possible have required different environmental permits.

However, the Finnish ReCreate cluster was convinced reclaimed elements could not be waste. After intensive negotiations and dialogues with the Ministry of the Environment, the Ministry published a landmark policy clarification: reclaimed elements do not automatically become waste if they are kept in a usable state throughout the process.

This general statement was coupled with further criteria. The Ministry established that “certainty of further use” could be proven without a specific building address. Instead, actors must show that the reclamation is systematic and there is demand for the products. The municipality of Kangasala then formally decided, using the clarification, that the reclaimed elements stored at the Consolis Parma plant do not constitute waste.

Beyond removing hurdles, the City of Tampere successfully tested a “land allocation competition” model, which ReCreate helped develop. In this system, developers who commit to circular methods (like reuse) are given preference in securing valuable land, providing a powerful financial incentive to innovate.

Sweden: temporary storage and chemicals

In Sweden, a similar interpretation of the waste status has not been reached as in Finland. Under the Swedish Environmental Code, reclaimed materials and products can only be stored for up to three years before the site is legally reclassified as a landfill. At the time of the report’s research, this issue was not resolved, and temporary storage remains a risk for the owner of the reclaimed elements.

In Sweden, much attention is paid to adherence to REACH legislation, because the developer bears legal responsibility for this issue. However, the Swedish country cluster received a clarification from the Swedish Chemical Agency that the limit values according to REACH restriction rules only apply to chemical products, such as cement. In this legislation, reused concrete elements are rather defined as goods.

The Netherlands: self-assessment of the waste status

In the Netherlands, the waste status of recovered elements has not formally been discussed in ReCreate’s pilot project. However, in the context of environmental permits, the project partner Lagemaat was obliged to use a self-assessment tool, to determine whether the recovered materials constituted waste. This tool followed similar logic as the Finnish authorities, and the outcome indeed was the elements would not constitute waste. The tool only offers guidance, however.

Germany: A case-by-case bureaucratic battle

The German regulatory situation is complicated because each state has differing regulations. The report therefore only deals with the states the pilot projects have been active in.
To some extent, the complicated issue in Germany revolved around quality assurance rather than the acceptance of reclaimed elements as building materials. The latter, through the site-specific permits, is possible according to existing German law. Regarding quality assurance, the issue was mostly which authority would be responsible for acknowledging the adherence to standards. At the time of research for this report, the issue was not fully clear. One further issue that is a potential challenge to the scalability of the reuse of reclaimed elements is the liability of owners for the materials. On the other hand, this could spur innovations in insurance products.

Common Themes: The Need for an “EU Umbrella”

All countries had very specific regulatory issues, but the ReCreate report identifies several common threads that affect everyone:

Quality management is probably the single most important issue for reuse regarding building permits.
Reusing materials currently requires significantly more negotiation and consensus-building than standard construction. This “interaction tax” is a hidden cost that currently burdens circular pioneers.
There is a unanimous call for the EU to provide a single, unambiguous definition of when reclaimed products become waste. Relying on 27 different national interpretations prevents the creation of a true cross-border market for reused materials.

In conclusion, the message to companies is clear: start early, negotiate and communicate often, and document everything. The path to a circular future is currently being paved—reused element by reused element—through these difficult but necessary regulatory conversations.

by ReCreate project

May 12, 2026

Aapo-Rasanen-and-Jukka-Lahdensivu-Tampere-University.jpg

Authors: Aapo Räsänen and Jukka Lahdensivu, Tampere University

Introduction to the reports: Procedure for quality management of reclaimed concrete elements, Properties and quality of precast concrete elements deconstructed in ReCreate’s pilots and Quality management best practices in reuse of precast concrete elements of the ReCreate project. The full reports are available on the website.

The ReCreate report Procedure for quality management of reclaimed concrete elements presents the six stages process for safe reuse of reclaimed concrete elements as a part of bearing structures in new buildings. The key process stages are:

Pre-deconstruction audit, where the main actions are finding out the type and number of elements, assessing their reuse potential, and gathering information for the next stages.

Structural investigation, where the main actions are ensuring material properties of elements primarily with non-destructive (ND) or semi-destructive (SD) methods, determining the condition of the elements, and finding out the existence of possible hazardous substances.

Deconstruction design and execution, where the determination of safe deconstruction and lifting methods is the main action, together with transportation and storage of deconstructed elements.

Full-scale testing is carried out if the structural capacity of reclaimed elements cannot be uncovered through other means or if there is doubt about safety factors. Also newly developed retrofit connections need testing if original connections cannot be reused.

Redesign and reassembly, where the main actions are designing the reclaimed elements according to Eurocodes and standards in force. Also, the refurbishment of the reclaimed elements must be designed and carried out before delivering elements to new construction site.

Product approval and authorisation is the final stage, where documents from the previous stages, together with technical drawings and calculations, will be presented to authorities to obtain official permits for reuse.

Visual investigation and thorough documentation are an essential part of each stage. Information must be carried through from stage to stage.

Properties and quality of reclaimed elements

Properties and quality of reclaimed elements were determined in four piloting countries: Finland, Germany, the Netherlands and Sweden. The report provides description of used test methods number of samples and measurements, and all test results carried out in laboratories of each donor buildings. In short, concrete grade used in reclaimed elements was higher than original design value, the elements were in good condition in general, and all found harmful substances could be removed before detaching of elements.

Knowledge Level

The ReCreate report Quality management best practices in reuse of precast concrete elements focuses on test methods and sufficient number of tests/samples needed for determining the material properties of concrete and the bearing capacity of elements. The actual condition, material properties, remaining service life, and probable repair needs of elements intended for reuse can be assessed through a systematic investigation. The need of testing depends strongly on the extent of available information. Therefore, four Knowledge Levels (KLs) are introduced:

Knowledge Level 1 (KL1): No information is available regarding the concrete quality, reinforcement properties, or the manufacturer of the elements.

Knowledge Level 2 (KL2): No information regarding the material qualities is available, but the manufacturer is known.

Knowledge Level 3 (KL3): Some specifications describing the concrete and reinforcement properties of the elements exist, but no further information about the manufacturer or quality control applied during production is available.

Knowledge Level 4 (KL4): Detailed archives of specifications describing the used concrete quality and reinforcement steel design are available, and both the manufacturer and its quality control system are well-documented.

The first two knowledge levels (KL1 and KL2) describe situations where no design specifications are available on the donor building. In these cases, extensive non-destructive testing (NDT) and destructive testing (DT) is required. For KL3 and KL4, partial or complete archives of original documents are accessible, and the specified properties only need to be verified through selective testing, reducing the workload.

Parallel test methods

Many different test methods are available for determining properties of concrete elements. Some methods are simple, while others are more complex, potentially causing more damage and costs. Additionally, the reliability of the tests varies depending on the method used. The testing methods used should always selected to suit each specific situation, based on the project’s criteria. The criteria may include, e.g. the type of element, required level of reliability, requirements of the new building, or the test methods available.

Ideally, the test methods should be selected to maximise the amount of knowledge gained while minimising costs and time. By using parallel test methods, reliability can often be improved by complementing each method’s shortcomings to create a more reliable aggregated method. In the report different test methods are presented for:

compressive strength evaluation of concrete

cover depth and diameter measurements of reinforcement

carbonation measurements of concrete

chloride content of concrete

corrosion of reinforcement

freeze-thaw resistance of concrete

deteriorated concrete.

The methods are presented in tables containing information on suitable standards, representativity, reliability, workload and number of needed tests of each presented test methods when the information is available.

Number of samples

Number of samples needed for each test are mentioned in standards in the first place. Several tests presented in report have no standard, e.g., cover depth measurements reinforcement. Sufficient number of test specimen or full-scale tests for high reliable results is based on scientific research on the results from the pilot projects. High deviation of test results gives a recommendation of higher number of samples/tests than the minimum number in standards. The recommended number of samples are presented in the report.

Conclusion

Quality assurance measures carried out in the ReCreate project varied somewhat across different pilots. The best practices presented in the report are based on the necessary actions taken at each pilot. In particular, damage and deficiencies in structural elements required significant interventions. These defects were discovered at different stages of the pilots, leading to immediate responses each time, which resulted in multiple actions being taken.

Overall, the quality assurance measures are especially useful in validating the reusability of elements. These measures will also benefit the structural designers by helping anticipate potential deficiencies and necessary modifications during refurbishment. Well-documented processes will provide evidence of reusability to authorities and other stakeholders involved in the reuse process. In Finnish pilots the developed quality management process was used successfully. The building inspection authorities in Tampere and Helsinki accepted the developed quality management process for reused concrete elements as a part of the site-specific authorisation.

by ReCreate project

April 20, 2026

Author: Satu Huuhka, Tampere University

ReCreate’s Finnish cluster announces the completion of its third mini-pilot! You can read about the first one here and the second one here.

The third Finnish mini-pilot was built during autumn-winter 2025, with the last reused elements installed in December. Like the first mini-pilot, this building is also a block of flats. It was built by Skanska in the new Tampere district Hiedanranta, with the housing provider ‘TA’ as the client. It involves 55 reused elements originating from the project’s donor building: 35 hollow-core slabs, 13 columns and 7 beams. As was for the second mini-pilot, Ramboll Finland acted as the responsible structural designer, and the elements were refurbished by Consolis Parma.

For hollow-core slabs, the reuse application was slightly different from previous. Whereas the first mini-pilot reused these types of elements as floors for residential spaces, this time they were mainly employed in the ceilings. Despite the distinct conditions, the mini-pilot provided no new major observations regarding reuse of hollow-core slabs vis-à-vis to the learnings acquired already in the previous pilots. The replication nevertheless served the important purpose of routine creation for the involved ReCreate companies, which is a prerequisite for mainstreaming reuse as a part of regular business operations.

This mini-pilot was, however, the first time that columns and beams reclaimed from ReCreate’s Finnish donor building were reused, even if in small numbers. Some learnings were acquired, but the practical conditions of the housing project also limited what could be achieved. Because there was no aim in the project for an open or adaptable floor plan, there was no architectural benefit to using columns instead of load-bearing walls. However, it still was an opportunity to test the columns and beams in a multi-storey building from a structural perspective.

Regarding hollow-core slabs, all the mini-pilots together validated the fact that at the construction site, their reuse is no different from using virgin elements. This is great news business-wise, as this kind of observation can lower the adoption threshold for construction companies, and hollow-core slabs could be a ‘low-hanging fruit’ of precast concrete reuse. Nevertheless, it should be noted that despite their seeming simplicity, hollow-core slabs are highly optimised engineering products, with little structural margin. Thus, their reclamation and quality management call for in-depth expertise about their structural behaviour.

Moreover, both the first and the third mini-pilots demonstrated the economic viability of reusing precast concrete elements in the context of affordable housing projects, which come with tight budgetary conditions.

ReCreate’s Finnish cluster is formed by Tampere University, Skanska, Consolis Parma, Ramboll Finland, Umacon, LIIKE architects, and the City of Tampere.

Video & photo credit:

Creamframe / Mikko Laaksonen

Tampere University / Eetu Lehmusvaara

by ReCreate project

February 24, 2026

Author: Satu Huuhka, Tampere University

ReCreate’s Finnish cluster shares news about its new mini-pilots. This is the second of them. You can read about the first one here. Stay tuned for more info on the third mini-pilot, which will follow shortly!

The second Finnish mini-pilot was implemented in summer 2025 in conjunction with the construction of the industrial production complex ‘Lokomotion Technology Centre’, which Skanska is building for the client Metso in the Lahdesjärvi district of Tampere. It involved reusing 27 hollow-core slabs in two buildings: a small self-standing building with technical spaces, and staff facilities located as ‘space within a space’ inside a larger industrial hall.

As opposed to the first mini-pilot where the elements were reused in intermediate floors, here the hollow-core slabs were employed in roofs. A different application of the same type of elements contributed to new learnings, as different requirements can posed on elements depending on where and how they are used, for example with regard to surface smoothness or outwardly appearance. In addition, different construction projects can have individual processual requirements for how the reuse is integrated as a part of the whole with elements made of virgin materials, regarding e.g. the assembly order and suitable assembly equipment. Organising logistics is another consideration when reused and virgin elements come from different suppliers, though this is not essentially different from regular building projects, which can also have a large number of suppliers for various construction products.

Like all elements in ReCreate’s Finnish reuse pilots, also the ones used in the second mini-pilot originated from the same donor building in Tampere city centre, originally built in the early 1980s and deconstructed by the ReCreate partners in autumn 2023. The distance between the original donor building site and the reuse site in Lahdesjärvi is 7 km.

Before reuse, the elements were refurbished by Consolis Parma. The ‘economy of scale’ of the second and third mini-pilots, together with the commercial reuse project that occurred in parallel, enabled Parma to temporarily dedicate a factory line in Nummela for the refurbishment of reclaimed hollow-core slabs. This helped to improve the efficiency of the refurbishment process, as opposed to the more customised approach of the first mini-pilot.

Ramboll Finland acted as the structural designer, responsible for all structural engineering aspects of the reuse in this pilot, including all the documentation for a site-specific approval process. The first mini-pilot set the foundations for how to conduct the approval process with the local building inspection authorities, and it was replicated in this pilot.

The mini-pilot successfully showcased the viability of reused elements in industrial buildings and as a part of a particularly complex and extensive construction project.

ReCreate’s Finnish cluster is formed by Tampere University, Skanska, Consolis Parma, Ramboll Finland, Umacon, LIIKE architects, and the City of Tampere.

Video & photo credit: Creamframe / Mikko Laaksonen

by ReCreate project

February 17, 2026

Authors: Jyrki Tarpio & Tapio Kaasalainen, Tampere University

A Circular Economy Course is held for fourth– and fifth–year architecture students at Tampere University each year. In 2025, the students’ assignment was to study how to reuse load-bearing structural precast concrete elements deconstructed from an office building in new-build multifamily housing. The Finnish deconstruction pilot building of the ReCreate project, the load-bearing structural elements of which were dismantled in 2023, acted as a reference donor building in the course.

Figure 1. Load-bearing elements of the Finnish donor building. Axonometric images and floor plan of a standard floor, excluding stairs. Image: Tapio Kaasalainen (adapted from an original plan drawing by Suunnittelutieto Oy).

A combination of hollow-core floor slabs, massive concrete slabs, columns, beams, and wall elements formed the load-bearing structure of the office building. Architecture students were asked to utilise these elements, bearing in mind that hollow-core slabs can be cut shorter or narrower and massive slabs shorter, but other elements must be used in their original size. Instead of being asked to design new buildings themselves, the students were handed drawings of two recently constructed apartments buildings in Tampere. Their task was to examine how to use the reclaimed elements as the load-bearing structure of one of the two reference apartment buildings maintaining its shape, main dimensions, and housing unit allocation (i.e. size and number of apartments). The main challenge was caused by the fact that the load-bearing structure used in both reference cases consists of walls and slabs, but the students had to mainly apply a column-beam-slab structure designed for a different building type and function. The task was limited to examining one recurring floor of one reference building per a student pair. To keep the workload manageable and focused, students were instructed to apply the reference buildings’ exterior wall structures as-is, even though in reality some modifications might be needed due to the altered overall structure.

Figure 2. Reuse applied to a rectangular apartment building. Column, beam, and wall reuse (coloured parts) shown on the left, slab reuse on the right. Design and images: Helmi Haapalainen & Viola Rytkönen.

Of the two references, the case ‘rectangular apartment building’ shared basically the same building depth as the office building, but its length was shorter. This made it possible to use nearly the same structural composition in the apartment building as in the original office building. The design by students Helmi Haapalainen and Viola Rytkönen (Fig. 2) reuses most slabs in their original or nearly original length, with two massive slabs and one hollow-core slab shortened notably and one hollow-core slab cut narrower. In the design, the locations of bathrooms and WCs are slightly modified so that they are concentrated in the middle of the building on the zone consisting of massive floor slabs. This arrangement is beneficial for organising plumbing and vertical building service stacks in a cost-effective way and also allows horizontal runs ”within” the inverted-U-shaped slab. The columns and beams are generally placed so that they don’t diminish the functionality of the rooms. However, in one room there is a slight aesthetic compromise with a beam running across it in the middle.

Figure 3. Reuse applied to the cut-corner apartment building. Column and beam reuse (coloured parts) on the left, slab reuse on the right. Design and images: Minttu Puustinen & Veetu Varala.

The shape and overall dimensioning of the other case, the ‘cut-corner apartment building’, was more challenging. Its frame depth is approximately one metre narrower and its length is shorter than the office building’s. However, students Minttu Puustinen and Veetu Varala proved in their design (Fig. 3) that, utilising the given columns, beams, and hollow-core slabs creatively, the load-bearing structure can be implemented successfully. They reused longer beams on both sides of the building and suggested a short new special beam in the middle of the building frame as well as shortened most hollow-core slabs—mostly cut only moderately, but some more extensively. The moderate cuts were similar in length to what might be required when salvaging some slabs in any case, although on the course all components were assumed to be as originally designed. Additionally, they narrowed one slab zone near the middle to fit the whole design into the required frame depth. With one exceptional column and beam location, they managed to fit the columns and beams along the party wall or walls separating apartments.

Concluding notions

Twelve groups of architecture students provided slightly different designs to the two reference buildings. In general, all students were able to grasp the idea of structural reuse with the notion that some additional material layers need to be installed on reused slabs and walls to meet the current soundproofing requirements of domestic spaces. As the final part of the course, the students made calculations on the embodied CO2 emissions and corresponding CO2 savings with their suggested reuse solution.

Most student designs had lower embodied emissions than the original reference buildings even without reuse (Fig. 4). This was largely due to the post and beam structure inherently reducing the amount of concrete used. Many designs also reused concrete panels from partition walls, in partition walls. These were thinner than are typically found in new construction, and thus even with added sound insulation led to lower emissions even for the ‘without reuse’ scenario which assumed virgin materials for the same structures. In contrast, however, in the same scenario a few student designs ended up exceeding the reference case’s emissions when concrete panels were used where not necessarily needed, such as under a beam along an apartment boundary.

Figure 4. Embodied emissions in the reference cases and corresponding student designs. Each design comprises a single storey of a single stairwell unit in the middle of a building. Thus there is no roof or foundations included, and floor slabs are only counted once. Each pair of columns corresponds to a single design, with the ‘without reuse’ scenario (all virgin materials) on the left and ‘with reuse’ on the right.

Based on feedback, the students found the course interesting and considered the skills acquired relevant for their future work as architects. Many specifically pointed out the technical design aspects and emission calculations as being important and at the same time something they had not learned to the same extent in other parts of the degree.

The course was organised in collaboration with ReCreate and supervised by Prof. Satu Huuhka, Dr. Tapio Kaasalainen, and Dr. Jyrki Tarpio.

by ReCreate project

December 15, 2025

Matias Pajarre, Tampere University

In the ReCreate project, groundbreaking work has been done in researching the technical, societal and economic feasibility of concrete element reuse. But still, it is also good to remember that we are not alone on this mission and there is a lot we can learn and have learned from others, both unconsciously and through intentional imitation. This topic might not seem attractive at first as imitation as a concept is often frowned upon and we tend to have a strong preference towards novelty, but this is exactly the reason why it might be good to stop to think about its importance.

How often is something entirely new in the first place? Innovation and imitation can be seen as two ends of a continuous spectrum where almost everything we do has an innovative element and an imitative element. For example, airfryers are a relatively novel product category that takes an existing technology such as convection ovens but brings novelty with a new form factor. In almost everything “new” we do we can see that we are just adding a varying degree of novelty to an existing product, process, technology or even capabilities.

Because of this, it is interesting to highlight the learnings we have received from others. In the interviews conducted for the WP7 research, many ways can be seen how existing knowledge from other fields and situations has helped us towards our circularity goals in ReCreate and also in a wider context. Here are some of them:

People transferring their previously learned skills to new situations

Even though the demolition workers deconstructing the Finnish pilot building were faced with a new challenge, they had already gained valuable experience from a different situation: disassembling paper machines. Because of this, they had developed important skills needed for the careful disassembly process without breaking the elements and the right attitude for the task.

While this is a relatively simple example, it highlights the way some fundamental skills can be transferred to surprising new contexts also for the benefit of sustainability. Especially in an era where the industry borders are expected to vanish when circular value chains start flowing more and more across companies of different industrial fields, there could also be much wider potential for widely applicable circular economy skills than just deconstruction work.

People carrying ideas across industries

While having widely applicable circular work skills might make work easier in diverse situations, it is also ideas and knowledge that can be useful across various fields. We have talked about how some companies and entire industries have been renewed by people arriving from different fields, sometimes with lots of experience on how things could be done in the ways commonly used in their previous work areas. This, in a way, echoes the long-known facts that more creative outputs are more likely from work teams with diverse backgrounds and individuals with knowledge from multiple fields.

Developing novel technologies and ways to use them

When new technologies arrive to the market, different trajectories and cases of exaptation can be seen where new use cases are found, both close and from the existing ones as the technological development advances. For example, drones are a technology originally developed for military purposes, but they are being adapted for many new tasks in different fields. In ReCreate, their potential for scanning tasks has been discussed.

We have also had talks about the prospects of using robotics and automation for various tasks in deconstruction work. The technology is already being developed for a similar task. Recovering elements from steel buildings has been noted to be much easier due to the connection types and indeed, robots are being developed elsewhere for that purpose. For concrete elements, however, the consensus in our interviews has been mixed so far with a fair amount of skepticism.

Despite the evident challenges in the automation of deconstruction, it is interesting to see what the future holds. A major technological change has already happened globally after these interviews with the way AI technologies have exploded in performance and popularity. I cannot tell if the development of AI will bridge the technological gap here, but we can certainly hope and keep our eyes open in case someone will come up with an innovation that could become a solution to some of our problems.

by ReCreate project

November 26, 2025

In this interview, we are speaking to Jukka Lahdensivu from Tampere University, whose work lies in WP4 in the ReCreate project. WP4 is focusing on new safety standards for reusing precast concrete components to promote sustainable construction practices. It captures the technical challenges and the practical goals of balancing safety, regulatory standards, and sustainability in the reuse of materials.

Can you explain the primary motivation behind creating a new quality management process for deconstructed precast concrete components?

Jukka: The primary motivation, in my view, is to demonstrate to customers and authorities that reclaimed components can be safely repurposed. It’s essential to ensure these elements meet safety standards when reused, and that’s why we’ve developed this process to verify their viability. We’re actively studying various aspects of these materials to ensure reliability.

How does this process differ from existing practices for virgin materials?

Jukka: There are quite a few similarities. In a factory setting, you test the raw materials, like cement and aggregates, before creating concrete and verifying it meets quality standards. However, for deconstructed materials, we’re testing the structure itself, often on-site, which is a big departure from standard practice with new materials. New components are generally tested during manufacturing, but here, the focus is on validating reclaimed components in their current state.

How challenging was it to integrate the investigation of harmful substances into the pre-deconstruction audit? What obstacles did you encounter in developing a standardized procedure for this?

Jukka: It wasn’t particularly difficult, especially since building renovations often require these studies before demolition. Finland, in particular, has a heightened awareness of harmful substances, likely because of extensive media coverage and prior issues with building materials. We’ve taken a thorough approach here, often exceeding regulatory requirements to ensure safety.

So, you would say people in Finland are more aware of these substances?

Jukka: Probably. It’s discussed frequently in the media, and we’ve faced issues in some newer buildings due to materials being enclosed prematurely. These problems have led to a deeper understanding and greater caution regarding harmful substances.

Work Package 4 focuses on ensuring reusable elements meet material and structural standards. Can you describe the testing process for these elements and their role in maintaining safety?

Jukka: We conduct tests on material properties before deconstruction to confirm the elements can be reused safely in new projects. This includes taking core samples for compression strength testing, measuring concrete cover depth over reinforcement, and conducting full-scale tests on beams and hollow-core slabs in the lab. These tests align with existing standards, ensuring consistency.

What are the key differences between assessing deconstructed versus newly manufactured components?

Jukka: With new concrete structures, we know the exact composition of materials. We need to analyse the concrete strength, reinforcement type, and other specifics for existing buildings. This lack of prior knowledge is the main difference when evaluating reused materials.

In this work package, you mention variability in material properties due to inhomogeneity. How do you manage these variations during testing?

Jukka: We conduct multiple parallel tests to gather a distribution of results. This approach is similar to testing new materials, but in a factory setting, components are consistently produced. With reclaimed materials, we often have only a few components to test, which means sample sizes differ from typical factory conditions.

Could you elaborate on potential challenges, such as deterioration, during deconstruction, transportation, or storage?

Jukka: We detected most deterioration, like cracking, in hollow-core slabs after deconstruction. These cracks weren’t visible in the building but appeared after detachment, likely due to the removal process. In Finland, we’ve also had cases where water entered hollow-core slabs, froze, and caused cracking. We had about six slabs damaged this way. When we removed the levelling on top of these slabs, accidental holes were created in the slab decks, though this was rare. In storage, however, we didn’t encounter any issues.

How do you decide on the reuse of these cracked components?

Jukka: It depends on the severity of the cracks. Small cracks with a width of 0.1-0.2 mm are often acceptable for reuse. Larger cracks, 0.3-0.5 mm or wider, need further assessment. We’ve created guidelines for visual assessment in the factory, and if significant cracking is found, a construction designer reviews it to decide on further action.

What are the most significant technical or regulatory hurdles in obtaining approval from authorities for reused components, and how might these be addressed in the future?

Jukka: The main hurdle is that authorities aren’t yet familiar with the requirements for approving reused components. We’re the first to bring this approach forward, so they’re unsure what documentation and standards to ask for. We’ve been holding meetings with local authorities in Tampere to explain our processes and the documentation we provide. This helps reassure them that we’re following a rigorous process to ensure the safety and usability of these reused components.

Best of luck with your upcoming meetings. Now, as we wrap up, what impact do you hope this work package will have on the construction industry’s approach to reuse and sustainability?

Jukka: Our goal is to develop a process that’s robust but not overly burdensome. Striking this balance is crucial to encourage widespread adoption of reused materials in construction.

Lastly, what inspired you personally to focus on sustainable construction and the reuse of materials?

Jukka: My research career has centered on the durability of structures—how they degrade and what measures can prevent damage. At our university, we’re also focused on adapting construction practices to climate change. While some researchers study climate change directly, we’re more interested in its impact on the built environment. Reusing materials is an important part of this, as it allows us to avoid new resource extraction and reduce environmental impacts, contributing to a more sustainable future.

by ReCreate project

July 9, 2025

Eetu Lehmusvaara,
Project researcher, Multimedia Creative Specialist
Tampere University

I worked as a videographer for the Finnish deconstruction pilot during autumn 2023 and spring 2024. I filmed the pilot project—a seven-storey office building located in Tampere—on multiple occasions during the autumn, which helped me realize the importance of documenting the stories of construction sites.

Consumers and users play an important role in the transition from a linear economy to a circular one. It challenges us to rethink what we value and what we don’t. And to value something, we need to understand it. Understanding requires experiences, and this is where videography can come into play.

The role of a documentary videographer is not only to show how things are but also to help people experience them. This is why seeing is not enough, emotions play a critical role in how we understand the world.

The Craft of Deconstruction

The craftsmanship behind deconstruction is something easily overlooked. To a passerby, a deconstruction site might look like any other building project. Cranes lift slabs, pillars, and beams, and workers move among various tasks.

But with a closer look, something different becomes apparent: Rather than building something new, the structure is being taken apart. The slabs, pillars, and columns are carefully removed and stacked like valuable resources, to be reused rather than discarded like waste.

When I first walked past the site, the loud but shallow clinks of hammers mixed with the high-pitched screeching of saws echoed through the building. These sounds were familiar from my previous visits to construction sites— but something about them felt different this time. I wasn’t sure what to expect. How would the workers perceive me? Would they be willing to be filmed? Were they proud of their work, or indifferent to it?

A moment of realization came a few weeks later. The workers were detaching an element from the building, as they had many times before. After about 30 minutes of effort, it became obvious that something wasn’t going smoothly. Seven men were gathered at one point on the building, all secured to the floor for safety, as they worked on the fourth story. One worker used a machine for extra leverage, others used circular saws and iron bars to free the element. The element was already attached to the crane, and the team was in constant communication with the crane operator. You could read the frustration on their faces, but their work remained precise and cooperative, as always.

Then it started to rain. I had to step away for cover, as did the managers who were observing the process. I waited under the stairwell for another 20 minutes, hoping to film the moment the element was finally lifted into the sky.

Sadly I missed the lift. My need to stay dry meant I missed the key moment of the lift. The construction workers, who didn’t have the luxury of stepping away, pushed through the difficulties and successfully removed the element—again.

Later, I realized the highlight wasn’t the lift itself. It was the story of skill and craftsmanship the workers demonstrated in making it happen.

Understanding Through Stories

To drive the shift toward circular construction, people need to see the work behind in it. We value historic buildings because they were hand-crafted, with all the imperfections that came with that. These structures tell stories, and their age gives them meaning.

The same goes for deconstruction. The knowledge and craftsmanship required to take buildings apart—carefully, responsibly, and with reuse in mind—is something people can value, once they understand it. This slow, demanding, yet environmentally positive work deserves recognition.

And for that, we need stories—compelling visuals and narratives that help us make sense of the world.

Hopefully, this short documentary can be one small contribution to a much larger shift.

by ReCreate project

July 4, 2025

Introduction to the report: Actor ecosystems and critical actors in precast concrete reuse of the ReCreate project. The full report is available here.

Authors: Lauri Alkki & Leena Aarikka-Stenroos; Tampere University

The reuse of precast concrete elements is gaining momentum as a sustainable practice in the construction sector. But what does it take to make this happen? Harnessing reuse changes the process of construction as well involved companies’ and other stakeholders, and therefore it is crucial to understand who the relevant actors are and what roles in a circular construction project are putting reuse to use. A construction project reusing precast concrete elements requires collaborative contributions from multiple complementary actors that can be considered as an “actor ecosystem” of concrete element reuse. Based on our case study examining several concrete element reuse projects from the organization and management perspective, we can share some insights on this. Let’s dive into the tasks and key actors forming the actor setting and actor ecosystem enabling reuse, driving this innovative approach.

Key tasks, actors and their roles in concrete element reuse process

To successfully reuse precast concrete elements, a variety of tasks along the full reuse process must be conducted by the construction actors with learning and problem solving-oriented and collaborative mindset. Each individual task is crucial in ensuring that the process runs smoothly from deconstruction to the final construction of new building(s) from harvested elements. Next, we explain the key tasks of concrete element reuse and the main actors contributing to them:

Planning the Deconstruction: This task focuses on planning the deconstruction (i.e., so-called reverse construction) implementation process and related logistical aspects, ensuring that it can be carried out safely and efficiently. In this task it is also essential to plan the necessary quality assurance actions that can be implemented already at the demolition site prior to deconstruction. In addition, when planning the deconstruction, it is valuable to take inventory of elements that can be detached to begin exploring their reuse potential. Key actors in this task are typically demolition companies and structural engineering companies planning the deconstruction, its implementation, and needed initial quality assurance actions as well as architect and structural engineering companies sketching the future usage of the potential detached elements.
Deconstruction: The actual process of dismantling buildings and extracting reusable concrete elements falls under this task. It requires specialized skills and equipment to ensure that the elements are not damaged during removal. Demolition companies with dismantling capabilities, knowledge and tools are the primary actors here.
Logistics: Managing the transportation and storage of deconstructed elements is essential to keep the process efficient. This task includes planning the logistics of moving elements from the deconstruction site to storage and then to the new construction site(s). Logistics companies and the actors operating at the deconstruction site (e.g., deconstruction companies) as well as the actors who are responsible for the intermediate storage (e.g., concrete element manufacturing companies) and the new site where the dismantled elements are going (e.g., construction companies) often handle this task.
Refurbishment, Quality Assurance, and Redesign: Once the elements are deconstructed, they need to be refurbished, quality checked and redesigned to fit into new architectural and structural plans in line with the client’s requirements and to ensure that the reused concrete elements meet all safety and structural standards. These tasks involve both creative and technical expertise to ensure that the elements are both functional and aesthetically safety to use such as building condition surveys already before deconstruction and after deconstruction testing the elements as well as refurbishing them to be ready to use. These tasks are closely related to the new building (partly) made from the detached and reused elements, since designers need to ensure that detached elements fit into new building designs and that necessary modifications and refurbishments can be carried out according to these designs. Manufacturing companies and structural engineering companies are most often responsible for the refurbishment and quality assurance processes, and architect and structural engineering companies are key actors in the redesigning processes with strong support from the construction company (and client(s)).
Reuse of the elements: Finally, the actual reuse of the deconstructed elements in new construction project(s). This implementation phase involves integrating the refurbished elements into new building designs at the construction site. At this task, it is essential to coordinate logistics and schedules regarding the factory refurbishment of reusable elements and the progress of the construction site so that the elements arrive at the site at the right time, ready for installation. Overall, however, installation is mostly carried out in the same way (possible minor differences in preparatory and finishing work depending on the details of the reusable elements), regardless of whether the element is new or reused. Construction companies play a key role in this task, as they are responsible for the operation and progress of the construction site.
Permitting and Regulation: Navigating the regulatory landscape shaping how easy or difficult it is to use the reuse principle is crucial for the success of concrete reuse projects. This task involves obtaining the necessary permits (e.g., demolition and construction permits) and ensuring compliance with local regulations (e.g., whether dismantled elements are considered waste or not, and what procedures can or cannot be used to utilize them), in collaboration with the relevant public authority and department responsible in the current situation, as well as the actors applying for the required permits. Local authorities, such as cities and their various departments (e.g. the department responsible for granting permits, developing zoning or promoting circularity through plot donation and acquisition), play a pivotal role in enabling reuse. This is achieved in collaboration with the owners of the donor and new buildings, who are responsible for applying for permits.

Depending on the reuse project phase, the division of tasks and the actors involved can vary (see Figure 1 for an example). The capabilities of each actor, their ability to collaborate, and the overall industry setting in their respective countries influence how the tasks are distributed and how the actor ecosystem organizes along the project. Furthermore, data collection, analysis, modelling, usage and sharing is a critical factor affecting positively the preservation of element value: therefore, actors should collaborate and ensure jointly that data is monitored and harnessed throughout the reuse process to support planning and implementation of each phase and reach optimized projects. In this regard, it is essential to gather relevant data to enable reuse, store the data in a way that allows for easy transfer, and ensure that all relevant actors have access to it. It is also important that these actors have the capability to analyze the data to ensure the safe usage of reused elements. Thus, open data transfer and communication ensures that actors understand what each considers valuable in the reuse process, avoiding the destruction of another actor’s value.

Figure 1. Example of an actor ecosystem enabling precast concrete element reuse: key actors per each process phase, their tasks and collaboration. The example is from the Finnish reuse pilot project in Tampere region.

Conclusion: the power of collaboration

The successful reuse of precast concrete elements hinges on a well-coordinated actor ecosystem with complementary skilled and collaborative minded companies and experts. Each actor brings unique expertise and competences to the table, which is why actor settings cany vary a lot depending on the case. Collaboration and knowledge sharing are essential to enable and optimize all tasks and process phases, and thus to ensure that concrete elements can be reused effectively and sustainably. All in all, as we move towards more circular construction practices, the insights from these pilot projects provide examples to think about how you should organize when planning to reuse concrete elements and repurpose existing materials to create a more sustainable world, in collaboration with skilled, future-looking expert partners.

The published deliverable and more detailed pilot projects findings can be found on the ReCreate and the studies behind this blog are also openly available here and here.

by ReCreate project

June 6, 2025

ReCreate blog post series on mapping in WP1

Post 4

Author: Niko Kotkavuo, researcher, Tampere University

To gain a broader perspective on the possibilities of reuse and ease knowledge and technology transfer across borders, one of the goals in the ReCreate project is to gather data on precast systems from various European countries. The work is not limited to the four pilot countries of the project (Finland, Sweden, the Netherlands and Germany), but also includes a selection of eastern EU member states known to have large stocks of precast concrete buildings. Besides residential building systems, the ones used in non-residential construction are of interest as well. This blog post series describes that experience. Please find here Part 1 of the series, which explains the nature of this work and describes the Polish experience, here Part 2, which discusses the Estonian experience, and here Part 3, which depicts the Romanian experience. The current post by researcher Niko Kotkavuo from Tampere University describes the Finnish experience and concludes the series, at least for now.

The Finnish experience

In Finland, post-war structural change, rural flight and resulting urban housing shortage led to high-volume industrialised housing construction beginning in the 1950s and culminating in the so-called ‘crazy years’ of the early 1970s. By the mid-1960s, most large construction companies had developed their own closed (company-specific) large-panel construction systems based on examples from abroad. In the late 1960s, to further cut construction time and costs, the concrete industry joined forces to develop an open system that any factory could produce.

The developed system, BES (short for betonielementtisysteemi, or concrete element system in English), was free to use by all operators in Finland. It soon became the new, widely adopted industry standard. In the early 1980s, it was followed by another open system Runko-BES (Frame-BES) for non-residential construction. While the systems have been updated throughout the years and their use has certainly became more versatile, they are still the basis for precast concrete construction in Finland today.

The wide adoption of BES and Runko-BES present a problem for reviewing the systems used in post-war Finland. Material on the BES systems is widely available and easy to access, and it covers a large portion of the precast concrete building stock in Finland. It is notable, however, that based on Mäkiö et al. (1994) and house construction statistics of central statistical office of Finland, the adoption of BES just missed the so-called ‘crazy years’ of housing construction. From the beginning of 1960s to the peak construction year of 1974, a large stock of buildings was constructed using the previous, closed large-panel systems, that are far less well understood.

Material on the previously used systems is significantly harder to come by, and details on the systems are seemingly forgotten in the existing literature. Thus, a more time-consuming approach of identification of specific housing projects, via literature review and by locating relevant construction drawings in municipal archives, has been used in studying the early systems.

Conclusions

Based on the very different experiences in the countries examined here, it is clear that there is no single approach for the review, which would work regardless of country. The work is, as is typical for archival work, quite reactive. In Poland, a large existing body of literature on the building stock made with large-panel systems could be capitalised on. In Estonia and to a lesser extent in Finland, there is a research gap regarding the composition of the housing stock in terms of precast concrete and system usage. In Romania, a lot of archival material has gone missing in the aftermath of the 1989 revolution which presented challenges, but university libraries provided useful catalogues and design manuals, which offer valuable insight into the country’s prefabricated building systems. A common factor for all four countries is that compared to housing, non-residential precast concrete systems and building stocks are a neglected area of study.

With the mapping of Finnish, Polish, Estonian and Romanian systems now complete we have a better picture of the systems used in each country as well as loads of archival material for later analysis, classification and digitisations of the building systems. This kind of work acts as a basis of future knowledge and technology transfer of the ReCreate learnings to new countries and regions.

References:

Mäkiö, E., Malinen, M., Neuvonen, P., Vikström, K., Mäenpää, R., Saarenpää, J. and Tähti, E. (1994). Kerrostalot 1960-1975 [Blocks of Flats 1960–1975]. Helsinki: Rakennustieto.

Tilastokeskus [Central Statistical Office of Finland]. (1974). Talonrakennustilasto 1971 [House Construction Statistics 1971]. Retrieved from https://urn.fi/URN:ISBN:951-46-0905-0

Tilastokeskus [Central Statistical Office of Finland]. (1975). Talonrakennustilasto 1972 [House Construction Statistics 1972]. Retrieved from http://www.urn.fi/URN:ISBN:951-46-1563-8

Tilastokeskus [Central Statistical Office of Finland]. (1975). Talonrakennustilasto 1973 [House Construction Statistics 1973]. Retrieved from http://www.urn.fi/URN:ISBN:951-46-1811-4

Tilastokeskus [Central Statistical Office of Finland]. (1976). Talonrakennustilasto 1974 [House Construction Statistics 1974]. Retrieved from www.urn.fi/URN:NBN:fi-fe2023013118667

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