Circular Retrofit Lab

- case studies and pilots in BAMB

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The Circular Retrofit Lab concerns the transformation of 8 students rooms in the middle of the green campus of the Vrije Universiteit Brussel (VUB).

Although the existing 352 student rooms were built as a temporary solution in 1973, they are still in use today and have become a cherished icon of the university. However, they have comfort levels well below current standards, primarily in terms of energy performance, contemporary comfort (kitchen and bathrooms are out-dated) and accessibility.

Today, the university campus is undergoing a transformation with several new buildings, in order to respond to growing numbers of students and to replace the existing student rooms. Consequently, the university initiated an exploration into how repurposing the existing student rooms can complement a sustainable development of its campus.

The housing units, designed by Van Der Meeren, are made by prefabricated concrete modules, and compatible infill components for exterior and interior walls. Each 96m2 unit (4 modules) consist of 4 student rooms, a common living space and kitchen, and 2 bathrooms.

Image: The loadbearing structure


The TRANSFORM research team will investigate and demonstrate how Reversible Building Design can prevent demolition waste when refurbishing existing buildings. Therefore it envisages 3 renovation strategies considering the re-design of these modules:

  • The internal transformation will test and showcase prototypes for a transformable internal
    organisation (partitioning walls, technical services, interior insulation, etc.).
  • The external transformation will add transformable external walls, demonstrating that
    reversible refurbishment meets current comfort standards.
  • The spatial transformation of the modules is based on the reconfiguration of the
    prefabricated concrete modules.


The goals of the Circular Retrofit Lab are twofold. First, when looking at all housing units on the VUB university campus, the Circular Retrofit Lab aims to act as a good example and catalyst for the future reconversion of the units in upcoming years.

At the building system and material level, the Circular Retrofit Lab aims to demonstrate how Reversible Building Design can prevent demolition waste and consumption of virgin resources while undergoing those adaptations in the future.

The overall objective of the Circular Retrofit Lab is to explore and implement pathways towards a circular economy in the building sector by integrating the concepts of reversible building design and material passports.


Within the above-mentioned constraints of the building structure, a refurbishment strategy is chosen with a maximal preservation of the existing tectonic of the façades.

A frame and infill approach is developed in which the building is stripped to the loadbearing structure and a new reversible infill is being introduced for the interior and exterior fitting-out:

  • For the partition walls, different wall systems will be developed/implemented in order to assess the technical feasibility, benefits and obstacles.
  • For the floors, two solutions will be combined. In a first stage, the floor is maintained as an integral part of the ‘building frame’. Besides, additional floor covering will be foreseen for certain zones/functions.
  • For the façade, two variants will be studied in relation to preassembly, reversible design, acoustical and thermal performance, and fire safety: a wood-based module and a steel frame.
  • For the technical services it is opted to work with visible elements in order to optimize the transformation capacity of the space of the Circular Retrofit Lab in the future.



The development of the Circular Retrofit Lab as an experimental lab for innovative reversible and reusable building solutions creates new opportunities for collaborations between the academic sector, the research sector and private partners.

These collaborations are an added value to the pilot’s objectives and ambitions. The expertise of private partners of the construction sector enabled to set larger goals and to integrate findings from the current building sector. The contact and collaboration with industrial partners also exposed new unknown reversible building systems and new opportunities.

Several product manufacturers and suppliers have already confirmed their participation to the project.


Business models and Circular Retrofit Lab

A building team has been set up for the construction of the Circular Retrofit Lab consisting of the VUB, Kaderstudio and Groep Van Roey.

Groep Van Roey joined as a part of the sounding board group in relation to the circular business models that can be developed based on the BAMB project’s results. In this context, VUB, VITO and Groep Van Roey are investigating if new circular business models can be developed based on reversible design principles. Therefore, two cases are analyzed: one where the building is owned as infrastructure, the other where the building is owned as investment.

The Circular Retrofit Lab – owned by the VUB – is selected for the development of the first case. The financial impact will be evaluated of transformability in building valuation and throughout the total building life cycle. Therefore, the initial investment (design and build), operation and maintenance (think of flexibility), and disassembly/transformation are taken into account from the point of view of different stakeholder groups (owner/investor, user/renter, supplier, facility manager).  Hence, reversible building solutions for e.g. wall partitions, can be developed in the future with a larger application in mind, namely as a building systems that can be interchanged over the total university campus.

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