De Rotonde Flat in Zandvoort: a complete building mapped from a representative sample
Anyone who has crossed the central square by Holland Casino in Zandvoort knows De Rotonde Flat. The building is a local landmark, an old and distinctive block that divides opinion: some find it ugly, some find it beautiful, everyone knows it. Buildings like this, with no current drawings but with concrete renovation plans, are exactly what CREW-B is good at.
How the project came to us
The contact did not come from a tender or from marketing, but from a chance connection. The chair of the owners’ association turned out to be the former work placement supervisor of one of our staff, from around ten years earlier. With the block now up for renovation, no usable structural documentation turned out to exist. The chair remembered his former intern, and that is how CREW-B came into the picture to capture the building digitally.
The challenge
De Rotonde Flat has fifteen floors with six apartments per floor, around sixty homes in total. Scanning every one of them individually was not an option: not every resident can be reached or is willing to take part, and it would have inflated the lead time unnecessarily. Because the floor plan of the block is entirely repetitive, we opted for a representative sample: on a number of different floors we scanned one apartment each. Placing those scans side by side produced a complete floor, and copying that floor upwards gave us the full building, without having to ring the doorbell of all sixty residents.
The facade is repetitive as well, so a representative section of it was enough to model the exterior in full. Only the ground-floor plinth called for a bespoke approach: it houses several restaurants and other facilities that were each scanned individually, because this part of the building is precisely the part that does not repeat.
Our approach
The scanning itself took about half a day, and most of that time went not into scanning but into calling on residents to get access to the selected apartments. The modelling, with a lead time of roughly two weeks, was more laborious than usual: instead of one continuous space we were dealing with a large number of separate scans that then had to be carefully joined together and stacked to arrive at one coherent model of the whole block.
The result
The client, Bouwteam P&O, received a BIM model as a structural base drawing: a reliable starting point with the right dimensions on which the renovation drawings can be developed. We also provided access to the NavVis IndoorViewer, which lets everyone involved, the architect, the municipality and other consultants, walk through the scanned apartments digitally, much like Google Street View. Instead of every party having to visit in person, the building can now be viewed and assessed remotely.
The project was delivered more than a year ago; the renovation itself has yet to begin. For CREW-B it was not the end point: Bouwteam P&O has since become a returning client, with several follow-up projects.
