Renovation of the Brunfaut Tower in Molenbeek-Saint-Jean
Introduction
Constructed in 1965, the Brunfaut Tower embodies rationalist architecture with its steel structure and 16 floors of social housing managed by Logement Molenbeekois. By 2015, various issues necessitated a complete renovation to meet modern standards of safety, comfort, and energy efficiency.
The renovation aimed to retain the total number of housing units while diversifying their types, ranging from studios to five-bedroom units. The project involved doubling the tower’s total surface area without affecting its impact on the public space in this dense neighbourhood.
To achieve this, the tower was extended vertically and its plan thickened, allowing for the ground floor to be freed and reaffirming the iconic presence of the tower.
The existing steel structure was preserved and exposed. A new bridge structure at level +18 supports the extension, relying on new lateral foundations. The new CLT wooden floors are lightweight and provide fire resistance, giving a warm aspect to the apartments.
The renovated tower is now a passive building with a high-performance new envelope. Precisely dimensioned frames and high-performance glazing ensure effective solar control. All two-bedroom and larger apartments (65%) feature patios bringing natural light into the heart of the units. A double-flow ventilation system and centralized heat production optimize energy efficiency. Technical rooms on levels +1, +18, and +22 reduce the size of technical ducts.
Special attention was paid to common areas: a transparent and accessible ground floor, convivial circulation areas with breathtaking views, a bridge floor with a multipurpose space and terrace, and a rooftop offering panoramic views and relaxation spaces.
The facades have retained their original smooth appearance, with a visually permeable ground floor, a distinct bridge floor, and a reflective, chameleon-like character, particularly thanks to a mirrored gable.
In sum, the renovation of the Brunfaut Tower represents an ambitious project that combines heritage preservation, technical innovation, and significant improvement in residents’ quality of life.
Urban Planning and Urban Strategy
The renovation of the Brunfaut Tower addressed the doubling of its surface area through vertical extension and plan thickening. This approach limited the impact on the public space of an already dense neighbourhood, freeing the ground floor and reaffirming the tower’s landmark character. The project aims to requalify the urban space by removing existing barriers, returning the tower to a scale close to its original state. Rather than expanding the building through an extension, which would have increased density, the choice of vertical extension was preferred. This option frees up convivial spaces for residents and neighbours while requalifying the tower’s surroundings.
Landscape Integration
To minimize ground impact, the tower has a highly transparent base. The new surroundings facilitate connection with the nearby Pierron Park and its universal accessibility. The south facade with its mirrored gable reflects the park's trees, creating a distinct visual landmark in the urban landscape. New plantings around the tower enrich the immediate environment.
Architectural Concept
The habitability of the housing units has been significantly improved. The apartments are more spacious, and 65% of them now feature new private outdoor spaces, patios, providing a pleasant and bright living environment.
Social Impact
Common areas play a crucial role in the tower's social dynamic. The multipurpose room on the ground floor will house a social grocery store, meeting the needs of residents and strengthening the community fabric. The multipurpose hall will host an association listening to the residents. The diverse apartment types, ranging from studios to five-bedroom units, perfectly meet the varied demands of neighborhood families.
Technical Aspects / Use of Wood
Wood reduces the weight of floors and facades, thus avoiding the need for extensive reinforcement of the steel structure and existing foundations, which would have been unrealistic, too costly, and complex.
CLT (Cross-Laminated Timber) panels were used for the new floors, with a total quantity of 1,500 m³. These 160 mm thick panels, half of which are a sacrificial layer in case of fire, meet fire safety requirements while providing effective acoustic insulation through the use of a floating floor system on rubber cubes. The exposed wood on the underside of the floors adds a warm dimension to the apartment interiors.
The detail of CLT slab supports, with a specific notch, optimizes free height under beams, which was crucial due to the limitations of the existing structure. At level +18, truss beams were implemented to transfer the loads of the new floors and manage the increased loads of the existing floors. This solution enhanced stability without excessively increasing the structure’s dimensions.
The wood ceilings could be left exposed in most spaces, allowing for a warm appearance while maintaining a good height and avoiding costly false ceilings.
The facade made of wood boxes filled with mineral wool, with a total surface area of 4,650 m², reduces weight on the structure, allows the use of prefabricated elements for rapid execution, and limits the environmental impact of construction.
The use of wood for the facades and floors not only improved the building's technical performance but also added an aesthetic and sustainable dimension, making the Brunfaut Tower a remarkable example of contemporary and environmentally respectful renovation.
