Blog posts - Recreate

February 17, 2025

The Refurbishing Plan developed by Lagemaat outlines a comprehensive renovation strategy for the Prinsenhof A-building that is being used as a donor building to transform it into the Circular Centre Netherlands (CCN) as the Dutch pilot project.

The plan addresses spatial integration, new site layout, and construction processes in Heerde. Temporary facilities, such as a mock-up and the Inspiration Pavilion, will be built to provide a realistic representation of the final design, to test the construction process and design details, and to allow visitors and stakeholders to explore the site. Additionally, a processing and sawing shed will be established to optimise space and facilitate refurbishment operations. The CCN design incorporates hollow-core slabs and façade elements. The façade elements are categorised into corner and middle elements based on structural application. The refurbishment involves uncovering external finishes and insulation to maintain structural integrity. A repurposed in-site tool will facilitate the processing and sawing of elements. Façade elements were cut, and the front parapets were removed from the structural elements with the saw wire. The parapets are then stored separately and stacked for clear and efficient organisation. Hollow-core slabs will be shortened using specialised equipment. This includes, among other things, cutting the elements using a specially designed setup tailored for shortening the slabs simultaneously. This phase ensures the elements are prepared for reuse without damage and in the same place where the CCN will be assembled.

Materials are managed with appropriate storage space to ensure easy identification and accessibility. This arrangement allows efficient use of logistics and space at the main site. The strategic approach aims to reduce risks, minimise costs, and enhance the overall quality of the project. This plan aims to ensure good practices for sustainable construction and future projects, aligning with the objectives of the ReCreate project.

by ReCreate project

February 13, 2025

The Finnish cluster has completed its first mini pilot in the autumn of 2024. The first batch of reclaimed elements – 25 hollow-core slabs – were reused in a block of flats in Tampere.

The building was built by Skanska for the client, affordable rental housing company A-Kruunu. The elements originate from the Finnish cluster’s deconstruction pilot, in which an office building from the 1980s was deconstructed in Tampere city center during the autumn of 2023. The new building with the reused elements stands in Härmälänranta district, Potkurinkatu street, about 6 km to the South-West from the donor building’s location.

Finnish mini pilot building

’It’s great to take part in a pilot that develops circular construction. The project corresponds to our aim to develop housing construction in Finland. The location in Härmälänranta is also attractive’, explains A-Kruunu’s development manager, Ms. Leena Oiva.

The reclaimed hollow-core slabs were reused as floors above an air-raid shelter, which was most suitable for the elements in this building considering the dimensions of the elements.

’Assembly of the reused elements was easy. It did not differ from using virgin elements. The frame of the building is fully precast, so there is further potential for reuse at the end of life.’ says Mr. Toni Tuomola, regional manager for Skanska, and continues:

’Skanska is committed to a green deal for circular economy. We will focus on reusing construction products by exploiting the learnings from ReCreate. The practical experience acquired from the pilot is therefore highly valuable.’

Reused elements were meticulously quality controlled and factory refurbished

Mini pilot installation

The elements reused in the pilot were quality controlled and factory refurbished in Consolis Parma’s factory in Kangasala, a municipality neighbouring Tampere. The first pilot produced invaluable learnings about the need for environmental permits when refurbishing and reusing elements, as well as quality control and product approval of reclaimed elements.

‘Climate change mitigation is at the heart of our strategy. Our aim is to halve our emissions by 2035. In ReCreate, we are looking into the business possibilities of reused elements and how it could contribute to our portfolio of low-carbon products’, shares Mr. Juha Rämö, technology director for Consolis Parma.

‘In addition to the factory refurbishment, we can contribute such core competencies to reuse projects as product design, storage, inspection, testing, and traceability’, Rämö continues.

Business development manager (refurbishment), Ms. Inari Weijo explains the role of Ramboll Finland:

‘In this mini pilot, we at Ramboll developed designing the refurbishment of the reclaimed elements in collaboration with the factory. We also took care of the site-specific product approval of reused elements towards the authorities.’

She elaborates:

‘We acquired useful learnings how to manage the process. This will come in handy in the next pilots and in expanding Ramboll’s service offerings in the field of reuse.’

Mini pilot floor

New pilots are being negotiated

The Finnish cluster aims to pilot reuse of reclaimed precast concrete in more than one building project. Different kinds of buildings and projects will contribute versatile understanding about the requirements for reuse in different contexts. Real-life pilots help to identify barriers to reuse that must be removed in order for reuse to become mainstream.

‘This mini pilot was a valuable first step towards more widespread reuse’, says ReCreate’s coordinator and the Finnish cluster’s leader, Prof. Satu Huuhka from Tampere University.

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

by ReCreate project

February 5, 2025

ReCreate blog post series on mapping in WP1

Post 2

Author: Arvi Rahtola, research assistant, 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. Beside 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. The current blog will discuss the Estonian experience, while the series will continue with Romania and Finland later on.

The Estonian experience

Master’s student of architecture Arvi Rahtola joined the ReCreate research team at Tampere University as a research assistant for a ten-week sprint in the summer of 2024, with guidance provided by project researcher Niko Kotkavuo, to collect material on the precast building systems of Estonia. This blog gives the personal account of his involvement and the challenges he encountered while studying the systems:

Challenges with mapping Estonian Soviet concrete construction systems were mainly related to the country’s rather small size. When country is so small that in most fields everybody knows everybody by name, very few things are written down. As a starting point, the available Estonian sources were mainly blogposts, old news articles, or commercial publications on insulating existing residential buildings. Even though the initial material was narrow, it led me to archives, which turned out to be well organized and easy to access.

Finding enough material didn’t turn out to be a problem. The design bureau responsible for designing most Soviet prefabricated housing left behind a large amount of records. Some type building series had over 200 folders of material to go through. The information I was looking for was hiding in four or five of them. Additionally, some of the archived material had unfortunately deteriorated to the point of uselessness. The main challenge turned out to be locating the relevant files while hoping they were in a usable condition.

Processing the found material ended up being a challenge. Having been part of the Soviet Union, where the main language of state and business was Russian, the found archival material was also written in Russian. During the process of finding material and interpreting the blueprints, I got to extend my vocabulary related to precast concrete construction.

Residential buildings in Soviet Estonia were built by the Union wide ‘type project’ system. This means that the same building could be found in Estonia or Kazakhstan. During all the Soviet period, Estonian prefabricated concrete housing was compiled of only few different Union-wide systems and two ‘homegrown’ ones. Compared to many other nations, everything in these buildings was strictly standardized, which made the review work easier.

An interesting aspect of Estonian elements is the use of ‘silicalcite’ concrete and the use of shale oil ash to replace cement. This was mostly because the concrete industry was already struggling to produce enough cement during the years of reconstruction after the Second World War. By using unorthodox materials, building capacity was increased, when ordinary materials were in short supply.

Most of the reuse knowledge about the pan-Soviet systems like the 1-464, or the 111-121, are also hopefully more widely useful. The former was in use everywhere in the Soviet Union, and the latter was also used in many areas; for one in Kyiv, Ukraine.

by ReCreate project

February 4, 2025

Leena-Aarikka-Stenroos-Mikko-Sairanen-Linnea-Harala-Lauri-Alkki_ReCreate-project_Horizon-2020-1.png

ReCreate blog post series on mapping in WP1

Post 1

Authors: Niko Kotkavuo, researcher & Maria Lomiak, research assistant, Tampere University

In the decades following the Second World War, many countries in Europe faced severe housing shortages. This lead to great efforts to industrialise building construction to reduce the cost and increase the speed of construction. The industrialisation effort manifested in many precast concrete building systems being developed, with various levels of standardisation. They became widely-used especially in multi-family housing construction in the second half of the 20th century.

Many of the systems follow national or regional borders while others have crossed borders. Border crossing has taken place e.g. via licence agreements or more unofficially, when features and details of existing exemplars have been borrowed in newly developed systems. Thus, the systems form an interrelated familial network. However, the fact that existing literature on the history of post-war construction has mostly been written in the local languages and for the audiences of the specific countries, is a challenge for the comparative study of precast systems.

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. Beside residential building systems, the ones used in non-residential construction are of interest as well. This blog post series describes that experience, starting from Poland in the current post, and continuing with Estonia, Romania, and Finland in the next postings of the series.

The Polish experience

Master’s student of architecture Maria Lomiak joined the ReCreate research team at Tampere University as a research assistants for a ten-week sprint in the summer of 2024, with guidance provided by project researcher Niko Kotkavuo, to collect material on the precast building systems of Poland. This blog gives the personal account of her involvement and the challenges she encountered while studying the systems:

In my hometown, Warsaw, large-panel construction is omnipresent in the cityscape. As a matter of fact, across the whole country, large-panel housing is becoming sort of an icon of the past. Though precast structures in Poland tend to be associated with poor technical performance and imperfections, they continue to serve their purpose, providing housing for almost 12 million people (approx. 1/3 of the population).

The findings on Polish industrialised building systems reveal a complex family tree of systems, with few central systems applied nationwide, and multiple regional systems. After the Second World War, the establishment of the communist regime in Poland led to the strengthening of individual cities and regions. Autonomous research centres and local manufacturers emerged, which resulted in unsuccessful attempts to centralise housing systems (Wojtkun, 2012). Aiming at socio-economic growth, the development of industrial technology focused on efficiency through limiting the number of building systems, but the realities of local conditions necessitated continuous modifications, leading to an increasing number of variations for each of the so-called central systems.

Therefore, the preserved material on Polish industrialised systems is extensive, though scattered across various libraries and archives. These prerequisites and limited time for fieldwork meant that when cataloguing and reviewing the Polish systems, a certain degree of prioritisation had to be done. Nevertheless, tracking down reliable sources was the most rewarding part of the job. Then, organising and translating the collected material was more tedious than I initially thought. Incomplete sets of technical drawings or intricate descriptions were some of the difficulties I encountered. However, a handful of industry-specific manuscripts and articles related to the subject allowed me to create a comprehensive dataset on central systems, which were prioritised during the research work. Archival journal articles provided general parameters of systems, but the differences between systems’ variations were documented poorly.

With that in mind, the potential reuse of prefabricated elements of large-panel Polish housing poses a serious yet achievable challenge. Pre-deconstruction auditing would probably require a better understanding of individual variations of the systems.

Reference:

Wojtkun, G. (2012). ‘Standardy współczesnego mieszkalnictwa’. Przestrzeń i Forma, nr 17, pp. 301–322.

by ReCreate project

January 15, 2025

Arlind Dervishaj, KTH

Concrete is used everywhere—in buildings, cities, and infrastructures. However, due to the large quantities of concrete used worldwide, it contributes to around 8% of global CO2 emissions [1]. While efforts are being made to reduce its carbon footprint, such as by using supplementary cementitious materials, an often overlooked solution is reusing concrete.

The ReCreate project aims to foster a circular economy in the construction industry by reusing precast concrete elements from existing buildings in new construction projects. To support this goal, our study investigated the reuse potential of structural concrete elements, evaluating three key factors: the remaining lifespan of concrete, natural carbonation (ability to reabsorb CO2 over time), and embodied carbon savings achieved by reusing it [2]. Reusing concrete has multiple benefits as it prevents waste, reduces the need for new raw materials, and significantly lowers life cycle CO₂ emissions. However, it is not as straightforward as it looks. The structural integrity of concrete with reinforcing steel can be compromised over the lifetime of buildings, if the right conditions for corrosion emerge, such as from the carbonation of the concrete cover and the presence of moisture at the rebar interface [3].

Circular Construction concept for concrete

Based on established carbonation models, we proposed a digital approach for estimating the remaining service life of concrete elements. The digital workflow also estimates the CO2 uptake from natural carbonation. We tested the workflow on an apartment building with a precast concrete structure, built in Sweden in 1967 during the Million Program. The building was modelled digitally, and material quantities and exposed surface areas of concrete elements were automatically extracted.

Digital workflow and building model

A key aspect of the study was the comparison of carbonation rates specified in the European standard EN 16757:2022 with rates derived from measurements in the ReCreate project and the literature [4,5]. This comparison revealed that the carbonation rates in EN 16757 may be overly conservative and hinder the reuse of concrete elements. We argue that relying on contextual carbonation rates, such as the ones in our evaluation, from a previous condition assessment, and new on-site measurements, is crucial for making informed decisions about concrete reuse. The study also addresses the recent RILEM recommendation on revising carbonation rates in standards like EN 16757 and CEN/TR 17310:2019 [6].

Using carbonation rates from EN 16757:2022, led to the conclusion that most of the precast elements would not be reusable (i.e. carbonated concrete cover and past the initiation phase for service life). The standard assumes a high rate of carbonation for concrete, especially indoors, which reduced the concrete’s remaining service life; concrete cover for indoor elements was expected to carbonate the earliest, 23 years after initial construction. However, when using the contextual carbonation rates derived from the ReCreate project’s investigation and recent literature, all elements were deemed suitable for reuse, with sufficient remaining lifespan. Plaster and other coverings slowed carbonation significantly, extending the service life of concrete. Additionally, carbonated concrete elements can be reused, but further considerations should be made concerning the environment and exposure conditions in the new building. Recommendations from ongoing research in ReCreate are expected for concrete reuse in new buildings.

The study also assessed the CO2 uptake of concrete over its life cycle, including the first service life, a potential storage period prior to reuse, and a second service life when reusing precast elements. The findings indicate that the CO2 uptake estimated using the EN 16757 rates was significantly higher than the estimate based on contextual rates. Additionally, the study demonstrated that the climate benefits of reuse exceeded those of carbonation, which accounted for less than 6% compared to the emissions associated with the production and construction of new precast concrete buildings. This highlights the importance of prioritizing reuse as a key strategy for reducing the climate impact of buildings.

Furthermore, the study investigated the implications of three different allocation methods for assessing the embodied carbon of concrete over two life cycles. The analysis included scenarios with and without carbonation uptake. The results indicated that the Cut-Off method was the most advantageous for reusing the existing building stock, followed by the Distributed approach, while the End-of-Life approach was the least favorable. The study emphasizes that the reuse of existing building stock offers a substantial opportunity for mitigating climate change and fostering a circular built environment.

Comparison of three LCA allocations, over two life cycles

References

[1] Monteiro PJM, Miller SA, Horvath A. Towards sustainable concrete. Nat Mater 2017;16:698–9. https://doi.org/10.1038/nmat4930.

[2] Dervishaj A, Malmqvist T, Silfwerbrand J, Gudmundsson K. A digital workflow for assessing lifespan, carbonation, and embodied carbon of reusing concrete in buildings. Journal of Building Engineering 2024;96:110536. https://doi.org/10.1016/j.jobe.2024.110536.

[3] Angst U, Moro F, Geiker M, Kessler S, Beushausen H, Andrade C, et al. Corrosion of steel in carbonated concrete: mechanisms, practical experience, and research priorities – a critical review by RILEM TC 281-CCC. RILEM Technical Letters 2020;5:85–100. https://doi.org/10.21809/rilemtechlett.2020.127.

[4] European Committee for Standardization (CEN). Sustainability of construction works – Environmental product declarations – Product Category Rules for concrete and concrete elements (EN 16757:2022) 2022. https://www.sis.se/en/produkter/construction-materials-and-building/construction-materials/concrete-and-concrete-products/ss-en-167572022/ (accessed November 26, 2023).

[5] European Committee for Standardization (CEN). Carbonation and CO2 uptake in concrete (CEN/TR 17310:2019) 2019. https://www.sis.se/en/produkter/construction-materials-and-building/construction-materials/concrete-and-concrete-products/sis-centr-173102019/ (accessed September 26, 2022).

[6] Bernal SA, Dhandapani Y, Elakneswaran Y, Gluth GJG, Gruyaert E, Juenger MCG, et al. Report of RILEM TC 281-CCC: A critical review of the standardised testing methods to determine carbonation resistance of concrete. Mater Struct 2024;57:173. https://doi.org/10.1617/s11527-024-02424-9.

by ReCreate project

January 8, 2025

An essay on a circular design by the Principal of LIIKE Oy Arkkitehtistudio, Eric Rawlins.

I recently posted a graph on social media displaying the percentage of recycled material used in construction across EU member states. Finland places second but last, with only Romania reusing less material in construction. Reactions were astounding, ranging from questioning the graphs’ depiction to demands to clarify what are the materials in question at all, to claims that circularity is a fringe issue since it isn’t linear, to how spot on this finding is, and how high a mountain we have to climb.

Finns are pragmatic, focusing often – pardon the pun – on concrete solutions rather than philosophical debates. To paraphrase Mies van der Rohe, “getting things done” is crucial, whereas pondering is not quite so.

Albeit that the ReCreate project is focused on technology, the practice of “getting things done”, in this case how to integrate refurbished materials into a linear practice, might be considered less of an end. After all, even at its most utilitarian construction is always a means to another end. While construction processes are often viewed as self-orienting, there are ultimately merely an end to a larger purpose. Subsequently, buildings are designed by architects for the purpose at hand, less than the construction technique available.

This forces us to consider what exactly are we attempting to achieve with the buildings we build, and why is a particular purpose justified, particularly in a circular future. If by definition we are motivated by a low-carbon world and premised by the availability of reusable material(s), should we not consider how necessary construction is in the first place? And then which purposes, solutions and outcomes can be considered acceptable?

Anticipating these changes suggests a transformation where architecture evolves from a service to a deeply analytical and creative act, subscribing value, creating purpose, and resolving outcomes within material constraints. The need to transition to a circular economy emerges from a century of change, pushing us to move away from 20th-century models and technologies. To relinquish what was, in favour of what should be.

ReCreate already indicates that partners and stakeholders are becoming increasingly aware of reuse as a viable and realistic solution for a sustainable future. Not to perhaps entirely replace the linear world, but offer a complimentary path. As communities grow increasingly aware of the environmental impacts of post-war growth, the integration of reused materials in construction is beginning to show as a route to the future. One increasingly resonates with younger generations less inclined to believe in the world views of post-war extractive regimes.

This paradigm shift also suggests a reinvention of design, building, financing, and regulatory practices, presenting opportunities in fields beyond the construction sector. Where traditionally people see waste, we see the literal and conceptual foundation for a shift in societal values, business models and design practices. Reusing precast concrete elements might not represent a leap for mankind, but it does represent a significant step towards circularity in construction.

Our preparatory design studies navigate some of the constraints and possibilities presented by the selection of concrete elements and structures, retrieved from the Finnish deconstruction pilot. The emphasis is to study how to create an architectural solution to a given layout, which remains as faithful as possible to an original new build solution. Even in early studies, we have identified promising design strategies aimed to explicitly display the refurbished elements, as well as defined lines of study regarding potential hybrid structures, which may lead to real-life solutions that most likely would not be considered otherwise.

Our aim is to use the constraint-driven condition to establish an architectural language that will visibly express the ethos of reuse and sustainability, and encourage a dialogue between the old and the new, where our pilot building tells a story of continuity and renewal.

While it is said that history does not repeat, it merely rhymes, one is tempted to see similarities between today’s world and the world of the avant-garde. Transitioning to circularity is a phase change. If history is any measure, employing deconstructed material is a new practice which will manifest as a reinterpretation of architecture. Just as in the early 20^th century, societal and technological evolution manifested in the work of Le Corbusier, Mies van der Rohe and Alvar Aalto resulting in a new architecture as a concrete outcome, a societal construct and a value expression, it would only seem only logical to expect something similar from the Green Transition.

In this case the use of refurbished concrete represents more than a technical solution to environmental challenges—it becomes a manifesto for societal change, literally embodied in the structures we inhabit. By reevaluating how we build and what materials we use, we can instigate a profound shift in values, business practices, and architectural design.

Our take on circularity in construction is one where, respecting what we have, our maxim becomes: Function Adapts to Form. To quote Alvar Aalto:

“Nothing old is born again. But it doesn’t go away completely either. And what once was will always be again in a new form.”

Eric Rawlins

Architect

Principal

LIIKE Oy Arkkitehtistudio

Figure caption: Reusing building material from the existing stock is first and foremost an opportunity. (Photo: Tampere University / Heikki Vuorinen)

by ReCreate project

November 22, 2024

Jakob Fischer, Brandenburg University of Technology

As Europe strives to meet its sustainability targets, the construction industry’s environmental impact is under increasing scrutiny. The sector is responsible for a significant portion of Europe’s resource consumption and waste generation. A key solution lies in evaluating building stock for its potential to contribute to circular economy practices, particularly through the reuse of construction materials like prefabricated concrete components. By reducing waste and conserving resources, this approach can help achieve the European Union’s (EU) climate and sustainability goals.

Europe’s Sustainability Goals and the Construction Industry

The European Union has committed to several ambitious targets, primarily through the Sustainable Development Goals (SDGs), including Goal 9 (Industry, Innovation, and Infrastructure), Goal 11 (Sustainable Cities and Communities), and Goal 13 (Climate Action). These goals promote building resilient infrastructure, reducing waste in urban environments, and taking urgent action on climate change.

In parallel, European policies such as the Circular Economy Package, the EU Waste Hierarchy, and the European Green Deal aim to curb resource extraction and promote material reuse. The building construction industry, as one of the largest consumers of resources and generators of waste, is central to these efforts. By recovering reusable concrete elements from existing structures, the sector can reduce its carbon footprint and contribute to Europe’s climate neutrality goal by 2050. The ReCreate project is developing numerous implementations to achieve these contribution goals.

Assessing Building Stock for Reuse

Evaluating building stock involves analyzing existing structures to identify materials that can be reused in new construction projects. This is especially important as Europe’s built environment contains vast amounts of materials, particularly concrete, that can be repurposed instead of discarded. The work package 1 of the ReCreate project is developing an analysis and mapping of existing precast concrete systems and elements.

Prefabricated concrete components, which are common in many buildings, offer substantial potential for reuse. These modular elements can be removed, inspected, and repurposed in new projects, reducing the need for energy-intensive production of new materials. Since concrete production is responsible for a large share of carbon emissions, reusing elements as a whole can significantly lower the environmental impact of the construction industry. Emission reductions of up to 98 % in comparison to virgin material prefabricated concrete elements, can be saved by reusing existing elements.

Urban Mining and the Circular Economy

Urban mining is a key element in transitioning towards a circular economy, where resources are reused rather than discarded. Buildings, especially those built in the mid-20th century, contain prefabricated concrete components that are still in good condition and suitable for reuse. Rather than allowing these materials to become waste, urban mining enables their recovery, helping reduce construction and demolition waste (C&DW).

C&DW represents nearly 40% of the total waste produced in the EU, underscoring the pressing need for robust waste management strategies. By reusing concrete elements as a whole the construction industry can contribute to a significant reduction in CO2 emissions. With concrete production accounting for up to 8% of global carbon emissions, any reduction in its demand has a meaningful impact on climate change mitigation.

Overcoming Challenges in Building Stock Evaluation

While the reuse of building components offers significant sustainability benefits, several challenges remain. On the one hand the structural and architectural integrity of reusable concrete elements have been testified and is being proven within the ReCereate project, however no market for reused elements has been developed yet, which could satisfy the demand of sustainable re-construction. Hence, the working packages 1 and 6 with the deliverable 6.2 will give an overview of the distribution and amount of defined elements in the existing building stock.

Another challenge is to evaluate the needed information for exact types of elements in existing buildings from national building stock databases. With the support of building owners (e.g. providing information on their building stock), reviewing literature and archives on construction/production activities in the past and assessing the current and future demolition rate, a more accurate assessment of the building stock will be investigated.

A centralized database tracking reusable materials across Europe could further enhance urban mining efforts. By cataloging the types, quantities, and conditions of reusable components, such a system would allow construction companies to plan projects more efficiently, ensuring that recovered materials are utilized effectively. Parts of these efforts will be achieved within ReCreate.

Conclusion

The systematic evaluation of building stock and the adoption of urban mining practices can contribute significantly to Europe’s sustainability efforts. Reusing materials like concrete supports SDG 9 by promoting resource-efficient infrastructure. It also aligns with SDG 11 by reducing urban waste and improving resource management, while contributing to SDG 13 by helping reduce the carbon emissions associated with new construction.

Achieving this requires collaboration between policymakers, industry professionals, and researchers. Governments can implement the regulatory frameworks and incentives needed to make reuse the norm, while construction professionals must adopt new approaches that prioritize resource recovery. Also building owners should be sensitized, to regularly evaluate their building stock, keeping track of their own ‘urban mine’ and step forward to interested planners and stakeholder in the construction industry with their upcoming potential of deconstructable and reusable concrete elements.

The future of Europe’s construction industry is circular, and evaluating building stock is a key step in realizing this transformation.

by ReCreate project

October 18, 2024

Arnaldur Bragi Jakobsson

Second Wind explores the potential of reusing pre-cast concrete elements from an obsolete apartment building in Helsingborg, Skåne County, Sweden.

As part of the ReCreate initiative, which encourages the sustainable repurposing of concrete components, I collaborated with Helsingborgshem, the city’s municipal housing company, to develop a new rowhouse typology of approximately 100 m², alongside a two-story multifamily apartment building on the same plot.
The project aimed to minimize modifications to the existing structural components, preserving their original form as much as possible while adapting them to new uses. The rowhouses, arranged in an L-shape with a southwest-facing courtyard, serve as rental units and highlight the potential of reused materials in creating modern, functional spaces. The apartment buildings, located on the north and south sides of the site, further demonstrate the versatility of these repurposed elements.

Throughout this process, I sought to maintain a connection to the original architectural context of the Drottninghög area, respecting its mid-20th-century character while introducing new, sustainable housing solutions. This project illustrates the significant environmental benefits and creative opportunities in reusing existing building materials, paving the way for more sustainable construction practices.

Rowhouse plan (Arnaldur Bragi Jakobsson)

by ReCreate project

September 27, 2024

Written by Linnea Harala & Lauri Alkki

The ReCreate pilot projects in Finland, Sweden, Germany and the Netherlands highlight diverse approaches to implementing concrete element reuse, each influenced by unique building types, contexts and organizational structures. An initial analysis by ReCreate’s business research work package (WP7) has revealed distinct patterns in these approaches, primarily categorized into centralized and decentralized models. During the ReCreate annual meeting in Zagreb, WP7 also organized a workshop to present the identified approaches to other project partners and to get feedback on the initial analysis.

Figure 1 & 2. Workshop between ReCreate partners at the annual meeting in Zagreb on the preliminary results of the two different approaches.

The identified approaches – A) centralized & B) decentralized

The centralized approach is characterized by a single key actor managing multiple phases of deconstruction and reuse. This model is most prominent in the Netherlands. There, the same actor is responsible for deconstructing a building and reusing most of its elements in a new structure, a process referred to as 1-on-1 reuse. The ecosystem in a centralized model is simple, with a central hub managing all operations. The key actor controls the flow of information and data mostly internally, ensuring streamlined communication and decision-making. In addition, the key actor’s business model extends to both deconstruction and reuse, highlighting its capabilities and resources. A strong single actor can oversee the entire project, facilitating optimized and controlled execution. With one key actor at the helm, there is a clearer distribution of tasks and responsibilities. On the other hand, success depends heavily on the performance and capabilities of the key actor.

Conversely, the decentralized approach involves multiple specialized actors managing different phases of deconstruction and reuse. This model is evident in Finland and Sweden, where elements are harvested and reused in various buildings. The ecosystem in the decentralized approach consists of several specialized, complementary companies and organizations. Therefore, effective communication and data sharing between these actors has been identified as a critical factor for success. In the decentralized approach, each actor operates based on its expertise and specialization, contributing to a more diversified and flexible business landscape. The feasibility of the decentralized model depends on how well the project organization coordinates multiple companies. This complexity requires robust inter-organizational collaboration to ensure smooth transitions between phases, as multiple actors require more discussion to define responsibilities at different stages, at least initially.

Overall, it can be seen that in the centralized approach, the control of the dominant key actor can streamline operations, but it relies heavily on this actor’s capabilities. On the other hand, the decentralized approach, while more complex, offers flexibility and the potential to leverage a wider range of expertise. In both approaches, the work phases and tasks are largely the same, but their overlap and sequence may vary. Ultimately, understanding these approaches allows for better strategic decisions throughout the concrete element reuse process, promoting more sustainable and efficient construction practices.

by ReCreate project

August 30, 2024

Lina Brülls, Graduate Architect and Master’s Student in the Computer Science Program at Chalmers University of Technology

The master’s thesis “Resource-Driven Design” explores how the design process can be adapted to facilitate the reuse of structural concrete elements. Research done in the thesis indicates that current design and data processes are not easily translatable to reuse scenarios, where preexisting structural and geometrical attributes of materials must be considered. Based on this, three key research questions are formulated: identifying the necessary data for the reuse design process, developing a Grasshopper Rhino plugin for data integration, and applying this tool in case projects with the aim of optimising reuse.

The developed Grasshopper plugin, programmed in C#, enables data handling from Excel into Rhino. It generates structural modules from reused hollow-core and load-bearing wall elements based on desired design parameters. The tool was tested in three architectural projects on Siriusgatan in Bergsjön. Regular consultations with the ReCreate team at KTH provided helpful expertise and feedback throughout the development process.

The study’s findings suggest that integrating data early in the design process can improve the efficiency and feasibility of reusing structural elements. One key challenge encountered in this project was planning within the constraints of the generated load-bearing modules. Including glulam beams introduced necessary flexibility, enabling adjustments in level height and allowing the removal of some load-bearing wall elements.

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