Designed by GROOSMAN in 1979 and redefined half a century later by GROOSMAN.
De Coolse Poort stands at the city's most contested urban intersection, where two competing Rotterdam visions, Witteveen's pre-war axis and Van Traa's radical Master Plan, have never been fully reconciled. The tower was designed by Rob van Erk of GROOSMAN (then Groosman Partners). Built on the site where the famous Rotterdamsch Nieuwsblad building once stood, the tower quickly grew into one of Rotterdam's most recognizable silhouettes. As a rare survivor of brutalist office architecture from the seventies, it is known to Rotterdammers as the Red Kroot, Aubergine, and Red Beet, thanks to its striking red-purple facade of glass, steel, and aluminum.
Nearly five decades later, GROOSMAN was invited to redefine the building. The transformation into a multifunctional destination attracts new visitors, supports local entrepreneurs through flexible offices and shops, and provides welcoming spaces for city center functions. The municipality placed great value on the building's cultural and historical significance, which remained central throughout the development process. De Coolse Poort demonstrates that historic buildings carry collective memory and can be genuinely valuable for the future.
Layered Composition and Contemporary Transformation
The original design comprises a series of interconnected components: three main volumes, formed by glass-lamella facades, a core of profiled steel plate, a plinth built from a three-layered volume, and an entrance that functions as a living room on the street. The plinth at Binnenwegplein was ultimately constructed as a two-story main volume, with the ground floor featuring a transparent shop facade. This transitions into the entrance, prominently positioned at the corner, beneath 'De Vuisten'. The canopy that emphasizes the entrance is a continuation of the core, folded toward Coolsingel and also addressing it. With current requirements, the bronze-tinted glass is no longer applicable, as it is no longer available. Therefore, a maximised transparent glass with a high solar control value was chosen, which reinforces the volumetry in a contemporary way.
From Closed Parapet to Transparent Facade
The facade renovation transformed the building by opening the previously closed parapets into a floor-to-ceiling transparent facade. The old rubber profiles and glass panes were replaced with new, slender frames and high-quality solar control and energy-saving glass, representing a major step toward sustainability. The fully opened facade, combined with climate ceilings, provides new functionality to the building floors and made it possible to preserve the city's first Post-65 high-rise project.
"It is about restoring coherence across all scales. We incorporated the low-rise buildings at Binnenwegplein into the overall volume and restored the curtain wall. What was closed is now open, so that the connection from inside to outside is finally perceptible. Binnenwegplein is a hotspot in the shopping district, and that calls for a building that opens up to it." — Gert de Graaf, partner architect, GROOSMAN
