Cofraplus® 220: maximum lightness for the structure in the 14/15 Bata Institute renovation project

Detailed information

The past and the present

Building numbers 14 and 15, two production halls of the former Bata Shoe Factory in Zlin built between 1944 and 1949, were purchased by the City of Zlin with the aim to rehabilitate them for cultural purposes as the city was searching a new common location for the regional library, museum, and art gallery. As part of the city's industrial heritage, the buildings are protected monuments.

The project of transforming the historically most interesting factory buildings originated in the 1990s and started with the rehabilitation of Building 21, the Bata Skyscraper, from 2002 to 2004 which now houses the regional government and the tax office.

The idea was to create an integrated cultural centre as a living organism in this new, emerging part of the city. The cultural centre aims to preserve, present, and distribute the region's unique cultural heritage as an inspiration for human creativity.

The renovation concept and the realisation

In an open architectural competition, the design of ADNS Productions Architecture was chosen for the realisation. It was based on finding a meaningful interconnection of the two buildings that provides a common identity for their three functions. The connection of the neighbouring buildings was realised through a platform, an open courtyard, which gives the space between the buildings a new proportion and function by providing space for sculptures, multimedia installations, conceptual art, or other cultural outdoor events. 

In order to fulfill its new purposes, the buildings required important internal transformations, structural renovation, and modern technical installations in order to ensure the sophisticated and energy-efficient concepts. Special attention was given to the structural remains of the building which had to be adapted statically to its new use.

Building 14 now houses the Regional Art Gallery and the Southeast Moravia Museum, and the Frantisek Bartos library occupies all of Building 15.

Cofraplus® 220: low weight, large spans, and easy handling

On the ground level of historical Building 15, an additional floor was introduced using a steel structure to achieve maximum lightness. Conceived as a slim floor system, it consists of ArcelorMittal's additive flooring solution Cofraplus® 220 supported by HEB floor beams with a plate welded to the lower flange and anchored to the existing columns. For the engineers and contractor, the challenge of this refurbishment project was in the joints of the existing round columns with the new flooring structure. These columns had to be made wider in order to provide the necessary supports.

Although the first calculations were planned with a different composite flooring deck, Cofraplus® 220 was chosen in the end due to its many advantages which include amongst others lightness, speedy installation, and cost savings. Furthermore, the installation of the floor in the existing building with restraint access for cranes and others machines fits well to the characteristics of this innovative floor system. Made of S350DG + Z 275 galvanized steel with 1.25 mm thickness and 750 mm length due to its specific shape, Cofraplus® 220 requires less slab reinforcement and less concrete compared to the previous solution. With spans from 5.75 to 6.15 m, the slim floor system was designed with a permanent load of 1.25 kN/m2, a live load of 6.0 kN/m2, and a fire resistance of REI 60. The concrete slab (NC30/37) measures 130 mm, and the total floor height is 350 mm. During construction, one prop per module was used.

In total, 1420 m2 of Cofraplus® 220 were supplied, and the ArcelorMittal Construction Team provided full technical and operational support for the calculations as well as on site.