Right from the start of the project, it was clear both to the client and to the architectural firm of the Frankfurt/Main-based AS+P Albert Speer + Partner GmbH that the property would not only radiate a high-quality appearance, but would also stand out at least as much on account of its environment-friendly and climate-friendly design.

The highest certification category of “Platinum” awarded by the German Sustainable Building Council (DGNB) was the benchmark right from the start – and it was achieved. The use of renewable energy resources for heating and cooling, photovoltaic modules on the roof and charging stations for electric cars and e-bikes all play an essential role as regards the sustainable orientation of these Company headquarters.

Terrazzo flooring covering 3,600 m² supports this high-quality appearance

The fine terrazzo floors are also characterized by longevity and durability when it comes to an assessment of the building’s life cycle: in the form of Korodur’s GRANIDUR BIANCO, the choice fell on a concrete floor that offers both an elegant appearance and functional advantages such as high load-bearing capacity and durability. GRANIDUR’s high-quality features are ready-to-use, coloured dry building materials for the production of polished, decorative screeds in a layer thickness of 15 mm or more. The area covers a total of around 3,600 m². Around 800 m² of this are accounted for by the foyer and around 2,800 m² by the corridors on four floors.

GRANIDUR BIANCO convinced the jury in a special test

The decision in favour of GRANIDUR BIANCO was made on the basis of the tests that the executing company, the design flooring specialists Estrich Schlag based at Föhren in Rhineland-Palatinate, organized for those responsible for the project.

Michael Schlag, Managing Director of Estrich Schlag and Chairman of the Federal Association for Screeds and Coverings (BEB), explained: “The client, HeidelbergCement AG, had laid down specific requirements. It was clear right from the start that the flooring had to fit seamlessly into its bright, friendly and inviting surroundings. Having the right aura played the main role in the selection of the test materials. So, along with the client, we looked at model construction sites already developed by our organization and then produced samples according to the client’s wishes.”

Steffen Benz, Head of Facility Management at HeidelbergCement, added: “In advance, we hadn’t yet decided on a specific look – such as the colour and gloss of the surface – but had checked several variations in grey and white. While other surface versions sometimes produced large-scale tinted shadows, the white terrazzo flooring used here impressed us right away. This screed fits harmoniously into the bright ambience of our new head office.”

Proven partnerships: HeidelbergCement, Korodur and Estrich Schlag have teamed up in numerous projects

Nikola Heckmann, CEO of the Amberg-based manufacturer Korodur, has her sights fixed, in particular, on the high quality and durability of the flooring produced at the HeidelbergCement site – after all, the two companies have already enjoyed a long and collaborative business relationship. For instance, Korodur procures various additives from the Heidelberg company. “We have been relying on raw materials from HeidelbergCement AG for decades. A good reason for the client to put its faith in the qualities of long-standing customers in this field too,” said Nikola Heckmann.

Korodur has also been working closely with the flooring company Estrich Schlag for many years now – including on this project. The experts from both companies always exchange ideas intensively, in advance, about materials, mixing processes and the ideal processing and machining of the building materials.

When installing the GRANIDUR BIANCO terrazzo flooring, for example, it had to be taken into account that the material had to be pumped over around 100 metres to the construction site and right up to the upper floors. Due to the high temperatures – which also increased in the dark tube during the transportation process – retarding agents had to be added to prevent the compound from setting prematurely.

Korodur heating screed is the basic component

Both the precisely-coordinated mixture of cement, sand and retarding agent and the use of a Bremat mixing and pump truck ensured that the screed could be placed and processed in the shortest possible time.

The basis for the GRANIDUR BIANCO surface was a fast-setting floor screed in the form of a heating screed containing the Korodur FSCem binder. This is a dimensional-stable, low-shrinkage (shrinkage class SW1 as defined by DIN 18560-1), fast-setting screed binder designed for the production of a screed that is usable and ready for laying after a very short time, the screed being, in this case, produced at an average thickness of 65-85mm.

Bernd Wagner saw to the site management on behalf of the Estrich Schlag company. Based on his many years of experience, he knows that “Dimension stability, which prevents shrinkage cracks, is essential for long-term quality. The ternary FSCem fast-setting floor screed has always proved its worth in this regard, and so we use it regularly."

Various “tone-in-tone” concrete solutions 

The terrazzo flooring was applied directly to the Korodur HB 5 bonding compound, which was specially tinted for white floors. In particular, when applying the GRANIDUR BIANCO decorative screed, the utmost artisanal precision was required – for example with regard to connections to the stairs, pillars and walls. The declared aim was to create the perfect impression of a “tone-in-tone” design with regard to all the concrete elements.

Bernd Wagner gives insights into the process for the production of the customized terrazzo appearance: “The polishing consisted of five cross-pass grinding steps culminating in a finish with a grit of 400 – the first three grinding passes in the dry process, the two finishing processes involving a wet process. We had to pay special attention to the peripheral areas featuring aluminium wall connection profiles and the built-in components – such as, in particular, spotlights. Here we worked with hand-grinders and a considerable amount of dexterity.”

The result was a practically pore-free, flawless surface that reflects the high-quality standards of HeidelbergCement AG.

Further information: https://www.korodur.de/produkte/granidur.html ;
 www.estrich-schlag.de ; https://www.heidelbergcement.com/de