Construction of an impressive mirror

Underneath the office building a 'mirror' had to be constructed, showing the reflection of the EPO office building in the surrounding water. An intensive and constructive collaboration between Dam & Partners, JP van Eesteren, Rots Maatwerk and MBI began. In the material selection process, a pilot plant was built to test the concept. With head-grade ceramics and excellent water management, a permanent mirror effect was created. As part of this intensive process, Rots Maatwerk went on a factory visit to Mirage, manufacturer of high-quality Italian ceramics, to learn all the ins and outs of ceramics.

Custom ceramic tiles

For the mirror of the EPA office building, over 8,000 m2 of ceramic tiles were delivered. This was a custom production to meet the client's requirements. These tiles were applied under water, which is a first for MBI on this scale. With a moisture absorption of only 0.02%, solid ceramic was the perfect choice for this particular project. In addition to the application, the size and desired effect were also considered, among other things. With a size of 120x60x2 cm, the ceramic tiles fully match the dimensions of the windows in the building. As a result, the lines of the building continue into the water. To achieve the “mirror effect,” the tiles are produced in a smoother version (R10). Normally MBI delivers outdoor tiles with higher skid resistance (R11 or R12) for minimal slip risk. Because the tiles at EPO Rijswijk will not be walked on, the R10 version was the right choice for this project.

Implementation

The tiles are processed on adjustable tile supports about 25 to 30 cm high. By laying the tiles approximately 5 to 10 cm below the water surface, the mirror effect is enhanced. The adjustable tile supports have spacers of 5 mm on top, so the joint distance is consistently 5 mm. This makes perfect processing possible.

Ceramic waterfall

In addition to the custom tiles, ceramic slabs were also used in the work. The slabs of no less than 160x320x0.6 cm and 120x278x0.6 cm were applied vertically in a waterfall of more than 300 meters long. These Mirage slabs are finished in the same color as the ceramic tiles of the mirror and perfectly match the dimensions of the windows in the building. The execution required precision and attention to detail. Processing the slabs is extremely specialized work that can only be carried out by absolute specialists. Due to the impressive length of the concrete substructure, dilatations were necessary. One of the challenges here was that ceramics and concrete have different physical properties. For finishing, the slabs were grouted with a special grout.

For the horizontal part of the waterfall, custom-made covers were produced by Mirage. These are quarter-round finished and slightly inclined so that the water “runs” over them and does not fall. Continuity was also very important with the covers. The slabs were used as a starting point for the covers, so color and texture matched perfectly with the rest. The dimensions also had to match perfectly so that the lines of the windows, tiles and slabs continue. As with the slabs, special primers, mortar coats and adhesives were used to process these tiles. Again, this work can only be carried out by the absolute specialists.

Cooperation and challenges

EPO Rijswijk is a wonderful result of intensive cooperation between specialists. From first contact to completion, a total of about 4 years, there has been continuous consultation between the architect, contractors, MBI and Mirage. To get the mirror to what it is today, a trial installation was built to test everything extensively. During the four years there were many challenges. One was the central location. There was little room for a large construction site, so all materials had to be delivered just-in-time. Moreover, despite the enormous custom production with different production runs, everything had to be produced in the same color batch. This meant that no color differences could occur between the different materials. After all, continuity was very important. The execution came with its own challenges such as the sucking and blowing force of the wind and sloshing action of the huge water surface. Finally, the work of the parties involved had to fit together perfectly and comply with EPO's very strict safety procedures. Through constructive cooperation, and the end result speaks for itself.