Roof renovation with a complete solution from BEMO

The renovation of the roof presented a number of challenges. For example, it is a very flat pitched barrel roof that required very long standing seam sheets without cross joints. In addition, it was not possible to interrupt ongoing operations, so the refurbishment concept could not interfere with daily shopping.

After the roof refurbishment, the new metal roof had to be durable, recyclable, low-maintenance, penetration-free(without visible fasteners) and at the same time economical. Therefore, a modern standing seam roof was the ideal solution. Due to the length of the standing seam sheets being up to 52 m, on-site production was suggested.

With the BEMO standing seam profiles a minimum roof pitch of 1.5° can be realised, which can also be reduced further with local limitations,, for example in the ridge area of a barrel roof. In order to ensure maximum safety in this area, the profiles were equipped with an EPDM bead seam seal.

The roof refurbishment went exactly according to plan. After delivery of the coils and the roll former, the dismantling of the defective parts of the roof was started immediately. During this process, the formwork was inspected and refastened and a new vapour control layer was laid. On the basis of the detailed installation plan prepared by BEMO, slip-optimized BEMO GRP supports were installed to ensure unhindered thermal linear expansion of the profiled sheets.

The production of the standing seam sheets with the roll former was carried out suspended at from a crane, directly onto the roof surface, so that a tight and secure roof was already in place in the evening. Acoustic insulation was installed between the standing seam and the separating layer. This reduces extraneous noise and ensures permanent acoustic decoupling. Furthermore, slight unevenness of the formwork was compensated for and all welded connections could be made safely and easily without any additional dimensions. In addition, the risk of damaging the separating layer during the welding process was eliminated.

All penetrations in the roof area, such as skylight domes, ventilation ducts and vapor pipes, were welded into the profiles on site. Special attention had to be paid to the floating installation of the flashings and the planning of the fixed points.

Due to the long standing seam lengths, an optimised sliding and expansion concept was developed in advance by the technical BEMO team. The focus was on optimising the sliding and fixed points of the roof.

The ingenious overall concept worked out completely and was even surpassed by the roof renovation – with the highest satisfaction of the owner and operator as well as the executing specialist companies, who even undercut the agreed time window of the entire renovation.

In addition to the new tightness, a roof safety concept planned by BEMO also ensures safe access to the roof area for necessary maintenance work on the SHEVS and ventilation systems.