Case study - The Resource Rows, Denmark

As mentioned earlier, material reutilisation or upcycling is one of the ways how the construction industry can adopt a more circular and greener approach. This case study offers an example of how this can be applied realistically to the current construction methods. The study concentrates on a residential complex called “The Resource Rows” located in Copenhagen, Denmark (Figure 17). The project is a collaboration between the Lendager Group and the Arkitektgruppen. The Lendager Group is an architectural office with a long history and expertise of adopting circular ideas into construction designs (Lendager Group, nd). The Arkitektgruppen or AG Gruppen is a privately-owned Danish company focused on a variety of construction-based services from project development to turnkey contracts (AG Gruppen, nd). Other partners in the process are the developer company NREP and engineering consultant firm MOE.

(Kozminska, 2019)

Fig. 17: The Resource Rows (Lendager Group, nd)

The building’s characteristics

The construction of the area started in 2015 and was finished in 2019 (Lendager Group, nd). The final residential complex has a total surface area of 9148 m² and consists of a total of 92 residences (Lendager Group, nd). Out these 29 are houses including terraces and 63 are regular apartments (Figure 18) (Arkitekturbilleder, nd).

Fig. 18: Structure of apartments (Wilson, 2019)

The materials

The Resource Rows offers a fine example of material upcycling and modern solutions to an eco-friendlier construction process. Reducing the CO2 footprint of the building was one of the leading triggers when designing the apartment building complex. This was achieved primarily through collecting a large portion of the material used from recycled sources. For example, the façades are built out of bricks that originate from various places, including the Carlsberg breweries, an old school as well as industrial buildings (Arkitekturbilleder, nd). Since separating the bricks from one another is an impossible task due to the wide usage of cement-based mortar, the architects decided to cut the brick walls into modules instead. These modules of 1x1 metres (Figure 19) were then used for the construction of the façade (The Resource Rows, 2019).

Fig. 19: The resource Rows building with recycled wall modules. (Gonon, 2019)

The total surface amount of façade that was built using this technique of cut-out brick modules was 3000 m², according to Anders Lendager. (Lendager & Vind, 2018) The steps taken to create the modules can be seen in Figure 20. This includes cutting out the wall parts of 1 m² each, fitting them into a 3 m² mould which was finally cast into concrete. These 3 m² moulds were then anchored on a welded steel frame. Using brackets, the whole element was then anchored to the internal wall and insulation.

Since the components were prefabricated, it allowed the construction process to proceed at a faster pace.

Fig. 20: The steps of assembling upcycled brick walls into modules. (Wilson, 2019)

The figure above further explains the various steps taken in order to create the explicit brick modules used for the façade of The Resource Rows. Although the preparation process involves a few extra steps, the actual attachment to the frame of the construction is achieved surprisingly fast, possibly even more swiftly than with regular brick walls.

The implementation of façade with bricks running both horizontally and vertically, as shown in the Figure 19, has been used before by the renowned Finnish architect and designer Alvar Aalto in his summer residence, Muuratsalo Experimental House (Figure 21). Aalto’s design was used as an example and source of inspiration for the creative use of bricks in the project of The Resource Rows (Lendager & Vind, 2018).

Fig. 21: Muuratsalo Experimental House designed by Alvar Aalto is used as a source of inspiration for the upcycled brick modules. (Rieke, 2012)

The wooden materials used to build the terrace areas, wooden parts of the façades, floors and balconies were acquired from the metro of Copenhagen during its expansion and renovation process. The total amount of wood material rescued for the building complex was 300 tonnes which would have otherwise been turned into waste. The wood was then processed in order to make it weatherproof as well as resistant to fungus and insects. The terrace areas and rooftops of the buildings are connected by metal bridges which are rescued from an old shipyard in Sweden. (Wilson, 2019) The roof area of the building consists of multiple greenhouses which have been built out of upcycled glass material. The recycling of materials used mainly for the exterior parts of the building does not only bring down the CO2 emissions of the entire building process, but it also gives the building a unique and modern appearance.

The design groups collected all of the materials and products used in the construction in a catalogue where they calculated the value of the materials CO2 wise, as waste and as useful construction material. This will allow better evaluation and re-utilisation of the materials after they have been disassembled from their original locations.

Other environmental aspects

Other environmental aspects that were taken into consideration during the design process were the conservation of energy and water. The building is built in a way that saves up energy costs, for example from heating, leading to direct economic savings.

The water system of the complex is also somewhat unique since it collects the rainwater from unused areas of the roof and uses it for irrigation of the greenhouse plantations as well as toilet flushing in the apartments. This also allows the residents to save on living costs.

In a conference held in Helsinki in 2019 one of the owners and main architects of the Lendager Group, Andreas Lendager, presented a calculation according to which the project saved up to 126 tonnes in CO2 emissions only by using recycled pieces of brick walls instead of building the walls out of new bricks (World Circular Economy Forum, 2019). This calculation did not even include the other reused materials and components. Using new bricks would result in an around 32 kg CO2 emissions while reusing and at the same time upcycling the bricks would produce just a fraction of that value with approximately 2 kg CO2 emissions (Figure 22).

Fig. 22: A comparison between the environmental impact between new and reused elements. (Lendager

& Vind, 2018)

The technique used to build the façade also allowed the unique design of it since the construction of such a complex pattern out of separate bricks would have been almost impossible and more importantly significantly more expensive.

6.2 Findings

As opposed to the building for disassembly concept where it takes a long period of time to benefit from the advantages it proposes, building with material reutilisation brings immediate benefits. Using materials that have initially been doomed to become waste is both beneficial for the environment, as presented in Figure 22 above, as well as cost advantageous.

While the total investment was not disclosed for this project, there are some financial details that should be taken into consideration. Reusing materials that have little or no expenses is an advantage for this type of construction. Of course, one must also acknowledge the fact that even though the majority of materials used were acquired at very cheap costs, the design process to implement those materials into the construction is more complicated than that of a conventional building. This, in turn, increases the costs of the project. Furthermore, the logistics involved in transporting the materials or even collecting them should be taken into account. After analysing all of the facts mentioned above, one can conclude that the total costs of a construction project utilising upcycled materials could, in the end, resemble the expenses consumed by a regular, non-recycled, construction project. Therefore, more innovative designs such as this should slowly become the new norm as they do not only possess the potential to save expenses and lower the usage of virgin materials but also to add a particular sustainability aspect to the project. Especially the latter is becoming increasingly more attractive to the people making it thus an essential factor to be taken into consideration when planning a construction project.

There is an abundance of buildings that are planned to be demolished, and the method of upcycling materials is proving to be successful in minimising waste produced.

Therefore, a new programme should be introduced where, before a building is demolished, an assessment of existing materials should be conducted. This would allow for easier recycling of valuable materials and thus minimise the usage of new materials in newly constructed buildings. Having said this, it is worth noting that virgin

materials are most of the time cheaper and easier to access as opposed to upcycled materials, which, although theoretically free, include extra expenses due to transportation, harvesting and special planning. These additional costs could be significantly reduced if this type of material harvesting would be positively regulated by the authorities, thus making it more beneficial and accessible for a larger number of customers.