In Bussum, RAU Architects has transformed a former military school into the new home of De Groene Afslag: a place where hospitality, work, education and experimentation come together around the transition towards a new economy.
The existing military training complex is located in Buurtschap Crailo, a former defence site currently being transformed into a new neighbourhood. Rather than replacing the existing building, the project takes the structure itself as a starting point, transforming it into an open, light-filled and highly circular environment.
The programme brings together a restaurant, a 30-room hotel, meeting and event spaces, offices, flexible workplaces and educational facilities for De Veranderschool. Together, these functions form what De Groene Afslag describes as a Veranderhuis — a “house for change”: a place where companies, start-ups, public organisations and other actors can meet and work on transitions in fields ranging from construction and energy to healthcare, education and finance.
Transformation Through Reuse
The transformation of De Groene Afslag is driven by a simple principle: make use of what is already there.
The former military school has been opened up through interventions that introduce more daylight, transparency and connections between different parts of the building. At the same time, existing and reclaimed materials are incorporated throughout the architecture rather than treated as secondary additions.
This approach extends beyond retaining the original building. Components and materials sourced from elsewhere are given new functions within the project, turning the building into an assembly of materials with different histories and potential future lives.
An external circulation structure, conceived as an artwork connecting the different floors, incorporates authentic Bailey bridge components — a modular construction system originally developed for military use. Elements such as windowsills and swing doors have been recovered from a former hospital and reused within the building.
The result deliberately avoids the uniformity associated with conventional refurbishment. Existing elements, reused components, art and new interventions remain legible, allowing the history of materials to become part of the architectural character.
Waste Becomes a Resource
Some of the project's most unconventional materials are found where they might least be expected.
In the hotel, acoustic ceiling finishes incorporate plastic recovered from the ocean by The Ocean Cleanup. In the hospitality spaces, approximately two cubic metres of banknotes taken out of circulation by the German Bundesbank are repurposed as acoustic material. According to De Groene Afslag, the material represents around €180 million in former currency.
The gesture is playful, but it also embodies the project's broader approach: materials conventionally regarded as waste are reconsidered according to the value they can still provide.
The 30 hotel rooms extend this idea of experimentation into the interior. Each room is being developed by a different artist, making art and individual interpretation an integral part of the building rather than an addition applied after completion.
A Workshop for the New Economy
Circularity at De Groene Afslag is not limited to the physical building. Its programme is designed around exchange, learning and experimentation.
The first floor functions as a workshop for the new economy, bringing together companies, start-ups and other organisations in meeting rooms, offices and flexible workplaces. Together with De Veranderschool, these spaces support programmes focused on concrete societal transitions.
Elsewhere, meeting and event spaces accommodate organisations and management teams, while the restaurant, hotel and public programme create opportunities for more informal encounters. Education, hospitality, work, culture and business are therefore deliberately mixed rather than separated into individual zones.
This combination transforms the former school from a building with a singular institutional purpose into an environment that can accommodate different users and activities throughout the day.
Circularity as an Experience
De Groene Afslag approaches sustainability without turning it into a lesson in restraint. Art, design, reused materials and unexpected objects coexist throughout the building, making circularity tangible and approachable.
This attitude is particularly relevant to the transformation of the former military school. A place once dedicated to training soldiers has been reimagined as a place for learning how economic and societal systems might operate differently.
For RAU, the transformation demonstrates how an existing building can acquire a radically different future without erasing its past. By retaining the existing structure, introducing reclaimed components and finding new applications for discarded materials, De Groene Afslag treats the building not as a finished object, but as a temporary configuration of valuable resources.
The result is both a building and a testing ground: a circular mini-village where working, learning, meeting, eating and staying come together — and where the architecture itself becomes part of the transition it is designed to facilitate.
