Kelloggs Silohotel

New roof for the Silohotel

The former Kellogg’s factory site in the port of Bremen is undergoing massive structural change. Production of the popular breakfast cereals began here in Germany over 60 years ago. With a convenient location in Bremen’s harbour district, which simplified the import of grain and export of finished products throughout Europe, rapid growth was guaranteed and the company soon became one of the largest employers in Bremen.

In 2016, the factory had to close after five decades because declining demand meant that production facilities were no longer being used to full capacity. To counteract the deterioration of the huge site and save the historic and iconic buildings, a plan was drawn up for the entire harbour district. The so-called ‘Überseeinsel’ (Overseas Island) is a huge urban and neighbourhood development project. The revitalisation of the former factory buildings was a central task and, at the same time, a particular challenge. Kalzip systems were used for the roofing of the former grain warehouse and the neighbouring rice warehouse.

Eine Nahaufnahme vom Dach des Kinderkrankenhauses

From grain silo to hotel

The most astonishing transformation on the former Kellogg’s site has probably been that of the old silo. Where a few years ago up to 5,000 tonnes of corn, wheat or oats were stored for breakfast cereal production, there are now hotel rooms. Floors were installed in the old concrete columns for the intermediate floors, and recesses were milled into them, into which windows were then inserted.

Previously designed with a flat roof, the buildings were to undergo not only an energy upgrade but also a visual enhancement. Frärks GmbH was commissioned to renovate the roof landscape of the hotel and the adjacent former rice warehouse, which now houses offices and restaurants, as they were able to offer everything from a single source: the Kalzip roofing, the drainage system running partly behind the façade, and all bituminous waterproofing on the balcony framework of the tower room, the hotel balconies, the canopy, the loading ramp and the basement waterproofing.

The base of the silo roof consisted of a simple concrete ceiling. This and the roof area of today’s tower room were first expertly levelled by the Frärks team. The specialist craftsmen then installed a vapour barrier. To ensure safe rainwater drainage, the Kalzip roof requires a slope, which was created using hat profiles and system-compatible clips specially manufactured for the project. This structure also creates an intermediate space that was used to install insulation, thus meeting the desired energy efficiency requirements for both hotel roof areas – the former silo and the tower room.

Das Kinderkrankenhaus bei Nacht in der Vogelperspektive

Careful connection work

The final installation of the standing seam profile panels in the standard size 65/400 presented a number of challenges. Penetrations in the roof, such as those for ventilation and air conditioning systems, had to be taken into account, as did the historic Kellogg’s sign: ‘The sign was actually supposed to be removed. However, as it was to be preserved as a kind of landmark, the building permit stipulated that “the sign must not be dismantled”. Accordingly, the connection work had to be carried out around it,’ explains Pascal van Tübbergen, branch manager of Frärks GmbH in Nienburg. An internal drainage system was also to be installed on the roof of the new hotel, which was achieved by the installation team with a few expert moves on the inner corners.

From rice warehouse to office

The adjoining lower part of the building was formerly used as a rice warehouse. Today, it houses new, modern office space. With trusses as the original roof substructure, the specialist craftsmen first had to install trapezoidal sheets here. Here, too, a vapour barrier, E-clips and insulation were used before the Frärks team covered the roof with the same Kalzip system. The industrially prefabricated standing seam profiles were quick and easy to install.