It almost feels like you are switching from one theatre set to the next. In the shiny central foyer of the WTC, smart office workers are heading towards one of the many business units in the building. Right at the back, in the right-hand corner, there’s a door. Open it and you suddenly find yourself on a construction site crawling with workers wearing safety helmets and bright orange jackets. They are plastering the walls, installing systems and walking to and fro with materials. Erik van Beem, logistics foreman at Ballast Nedam, is doing everything he can to ensure the two worlds are kept apart. ‘We’re building Tower Ten next to, opposite, underneath and on top of the existing building. In the process, we’re trying our best to keep disruption for the hundreds of WTC tenants to a minimum.’
Tenth tower in megacomplex
Tower Ten is the latest extension to the WTC, which covers more than 150,000 sq. m. and has more than 300 tenants, making it the largest multi-tenanted business premises in the country. Tower Ten will add another 32,000 sq. m. to the megacomplex. To enable its construction, the existing WTC D tower has been completely stripped out, renovated and had ten new floors added. A completely new tower, with 22 floors, has also been attached to the D tower. The underground car park has been extended to reinforce the tower’s foundations and a bicycle park has been added. Finally, a lower section is being built to connect all of the towers together.
No shortage of challenges
The first floors of the brand-new tower have just been completed. This marks quite a milestone: construction work on Tower Ten started in November 2018 and completion was originally scheduled for one year later. ‘It’s like working on a postage stamp here, wedged in between Beethovenstraat, the A10 and Strawinskylaan’, explains Van Beem. ‘It’s a logistically complex process delivering and removing materials while also continuing to build.’ But that’s not all. Ballast Nedam also had some subcontractors go bankrupt and had to deal with the pandemic. ‘We certainly faced no shortage of challenges’, continues Van Beem. ‘Fortunately, we’ve always had a good working relationship with our client (CBRE Global Investment Management, Ed.). Everyone has pulled out all the stops to build a great tower. On the outside, people will soon see a stunning façade, but behind it lies an awful lot of blood, sweat and tears.’
We take a look in the underground car park, where all of it started. The challenge of adding ten more floors to the existing D tower called for significant reinforcement of the foundations. This involved inserting 130 foundation piles into the ground. ‘That was far from straightforward, because we had to deal with high groundwater levels and peaty soil’, explains Van Beem. ‘If you drove a pile into the ground like that without taking precautions, the car park would be immediately flooded. That’s why we had to install sheet piling and use two types of pump drainage to keep it all dry.’ Van Beem walks towards the entrance to the car park, ducking under the barrier. ‘Can you imagine – all the material for the foundations had to get through this tight entrance? The foundation piles had to be delivered in parts, because they would otherwise not fit through.’
Cherry on the cake
We walk through the building floor by floor – and it is only then that you can really see how much work has been done. Each layer is bathed in a sea of light that shines through the glass façade. The detailed finishing work is now in progress, including plastering the walls, putting the final touches to the climate ceiling and connecting the last systems. The central foyer of the tower – Tower Ten will have an entrance in Beethovenstraat – has already been partly tiled with natural stone. But it is the top floor that is the cherry on the cake. Surrounded by glass, this extra high storey provides a kind of 350° view over the city. In clear weather, you can even see the Dom Tower in Utrecht. ‘What a great spot!’, says Van Beem as he gazes into the distance. ‘I can’t help but be proud of this project.’
The overall completion of Tower Ten is scheduled for November 2022. In the meantime, we have already started on the relandscaping of the area around Tower Ten. We expect this to take until the end of 2022.