Construction permission has been granted for the Tour & Taxis Towers in Brussels, a mixed-use development designed by MVRDV for developer Nextensa. The project forms a central component of the broader Lake Side masterplan and represents the final piece of the site’s long-term redevelopment.
Rising to 126 meters, the dual-tower scheme will become the tallest building within the Tour & Taxis district. The development comprises 58,000 square meters of mixed-use space, organized into a 20-story office high-rise—set to house the headquarters of Proximus—and a 35-story residential high-rise containing 199 apartments. A five-story plinth connects the two volumes, integrating offices and public functions, while a central passage and atrium link the Lake Side neighborhood to Anna Bochlaan, reinforcing permeability at the ground level.
The project underscores an evolving definition of density that integrates environmental performance as a core parameter. As MVRDV founding partner Nathalie de Vries notes, the aim is to deliver “high-value, dense, mixed-use neighborhoods that allow for future flexibility… without sprawl,” while expanding the scope of “responsible density” to include carbon emissions.
That ambition is reflected in the project’s structural strategy. Recognizing the typically high embodied carbon associated with tall buildings, the design prioritizes reduction from the outset. Using MVRDV’s CarbonSpace tool (MVRDV is a 2026 CVU Sustainability Program Partner), the team evaluated emissions early in the design process, leading to a hybrid structural system in which a concrete frame is paired with cross-laminated timber floor slabs in the office building. Combined with lightweight façade elements, these decisions reduce both structural weight and the volume of concrete required for foundations.
The result is a projected carbon footprint significantly below that of comparable buildings. The project targets alignment with EU taxonomy criteria for sustainable activities, alongside BREEAM Outstanding, DGNB Gold, and WELL Platinum Core & Shell certifications for the office component.
At ground level, the integration of public services and active uses aims to ensure continuous occupation and engagement, reinforcing the role of the building not only as a skyline marker, but as a connector within the district. The project is conceived as a transitional urban element, mediating between adjacent residential and office zones. Its massing is defined by a series of irregular setbacks, shaped through light and wind studies, which introduce terraces at multiple levels and expand access to views and outdoor space. The modular façade, based on a 2.7-meter grid, supports flexibility in use over time, allowing the building to adapt as the surrounding district evolves.
As the final project within the Lake Side masterplan, the Tour & Taxis Towers consolidate a broader shift toward mixed-use, transit-oriented, and environmentally responsive urban development in Brussels.
Learn more at MVRDV.