No Danger of Ice Stalactites, Nestlé’s New Freezing Hall in Krupka Sealed with More Than 2.5 km of Aluminium Strips

The mission was clear. No moisture can get through. That is why Metrostav DIZ builders used, among other things, more than 2.5 km of aluminium strips to seal the new extension to the freezing hall in Krupka, Teplice. The formation of frost in the form of ice stalactites could endanger continuous operations. The hall will store frozen products of the Garden Gourmet brand made by Tivall CZ s.r.o., part of the Nestlé Group. Although the construction work was completed at the end of last year, the builders have not yet left the hall – in cooperation with the investor, they have to properly test and fine-tune the operating technologies.

During implementation, the expansion of the freezer hall proved to be a completely unique project. One of the biggest complications was the connection of the new reinforced concrete hall to the existing building, which is not thermally insulated and does not have a vapour barrier. Different building functions, different height levels, expansion joints and the need to ensure perfect insulation required many unconventional solutions.

“The designers did not have that much experience with this type of construction project, they underestimated the physical principles that come into play when buildings are connected. Freezer halls are usually built using the “box in box” system, where the building around the freezer is used to access the freezer from all sides. Here, one building is stuck to the other, which entailed the problem of expansion joints to deal with the possible movement of both buildings. We also had to solve the different height arrangements. We learned as we went along,” said Petr Lohniský, project manager at Metrostav DIZ, adding: “In addition, the designers had to be very cautious because the building is located in an undermined area.”

Every penetration of the freezer hall is a risk. All light and cable penetrations had to be sealed, so Metrostav DIZ builders used vapour-proof and waterproof seals, which are otherwise used in tunnels. In addition, 130 sprinklers (fire-fighting heads) had to be installed to meet a special fire protection requirement of Nestlé’s Swiss insurance company, which is not common in similar projects.

The overall sealing was also verified by two demanding blower door tests, which are used to test the tightness of passive houses’ envelopes. But the parameters were much stricter in this case. “However, everything will only be finally verified when the building has gone through all four seasons,” explained Lohniský.

Two foundation slabs are also a construction novelty compared to the old part of the production hall. The lower one can have its temperature altered using heating cables, to prevent the gravel subgrade from freezing and subsequently lifting the floor.

The whole project was extremely demanding not only from the technical viewpoint, but also in terms of hygiene requirements. As it is a food processing plant, strict hygiene standards had to be observed. Open sections could not be used, cavities could not be created and installations had to be placed on special mats so that the area underneath was washable. Since there could be no 90-degree angles anywhere to prevent dirt from getting stuck, all joints and corners had to be caulked.

A room called the “warming room” for employees working in sub-zero temperatures meets the work hygiene parameters for the intermediate warehouse. They transport pallets from the production line to the freezing section and from there through the airlock to the new dispatch section, which handles an average of 5–6 lorries per day. The new warehouse thus enables Tivall CZ s.r.o. to streamline logistics processes and save on costs for transporting products to an intermediate warehouse in Prague.

Nestlé is the world’s largest producer of food and beverages. The company operates in 188 countries and employs over 270,000 people. In the Czech Republic, Nestlé produces a wide range of food products, including chilled and frozen vegan and vegetarian Garden Gourmet meals at the Tivall CZ s.r.o. plant in Krupka, whose products travel throughout Europe and to markets in North America.

Contact details

Radim Mana
Metrostav Group Spokesman
Metrostav a.s. Koželužská 2450/4 180 00 Prague 8
T 266 019 715, M 601 110 376
radim.mana@metrostav.cz, www.metrostav.cz