Refurbishment respecting iconic design

Natural ventilation rhymes with technical requirements and aesthetics 

On Rotterdam's Kop van Zuid, the striking De Peperklip building has been fully restored to its former glory after a thorough and much-needed refurbishment. The facade frames were also replaced. These were updated with Renson's Invisivent NL top grille, which represented a perfect compromise between aesthetics, respect for the original design and the high technical requirements in terms of natural ventilation and acoustics. 

In the original design by architect Carel Weeber, the window frames at the bottom were fitted with heavy sus-boxes that ensured the natural supply of fresh outside air, but at the same time had to keep out the noise. Aesthetically far from being the most beautiful solution, but above all a form of ventilation that the residents of De Peperklip appeared unable to cope with. Considered irritating, they were often glued shut. And that, of course, was disastrous for the indoor climate in the apartments.

"Mounted as a top grille on top of the window frame, the Invisivent NL aesthetically means a world of difference from the large louvres of the past," clarifies Clara Froger (design architect). "And this while still being able to meet all the technical requirements. With Renson as the manufacturer, it was a relief to notice how they understood what the issues were for this particular project. And how they thought along based on that in the effective realization."

For new construction and renovation

Willem-Jan Paijmans (technical architectural consultant Molenaar & Co Architects): "Architects and clients prefer the natural supply of fresh outside air whenever possible. You often have to work a little harder to meet the EPC standards, but if that means a more comfortable indoor climate for the end customer, I am happy to do it. Unfortunately, you don't always make it in terms of EPC with that either."

Yet, according to Jan Smit (project leader facade builder Rollecate), there is also a lot of potential for the Invisivent NL grille in the huge arsenal of homes in need of renovation in the Netherlands. Existing natural supply systems can easily be replaced there with considerable aesthetic added value on top. In combination with CO2-controlled removal of polluted indoor air, they help to provide the best possible indoor climate.