Kröpcke Center in Hannover

Special attention was paid to quality regarding preventive fire protection when renovating this shopping center.

The so called "Kröpcke Center" was built in the city center of a major town in Northern Germany in 1972. Under the new management a fundamental refurbishment took place between 2009 and 2014. The "Conlit"-System made of non-combustible ROCKWOOL stone wool takes care of the preventive fire protection of the steel elements.   

Originally the Kröpcke-Center was a multiple stepped skyscraper complex with shabby exposed concrete as well as massive and dark structures. Due to the refurbishment, which has been conducted in two construction stages, 19.000 m² of retail and office spaces were created. The modification of the five-storey building, however, was not purely external. The quality of the "internal values" was very important, too, especially with regard to preventive fire protection.

Lightweight fire protection boards facilitate logistics and installation

All steel columns and steel beams in the new Kröpcke-Center were covered with ROCKWOOL Conlit Steelprotect Board Alu. These pressure resistant insulation boards are one-sided covered with a grid-reinforced aluminium foil. Depending on the U/A-value of the steel component, they were installed in one or two layers of 25 mm or 35 mm.   
During the installation, the fire protection team did not go for the popular adhesive variant, but preferred to use the screwed installation method. The latter is independent of temperatures and therefore allows for a fast progress, even during cold winter months.  

Economic and fast installation in F 90-A-quality

Despite the enormous dimensions of the construction site, the easy and clean cutting of the insulation boards - a standard cutter-knife is enough - ensured a quick progress, even in areas where many details needed to be integrated into the fire protective construction. One example for this are the flanges between the steel beams and the new concrete façade that received a "Conlit"-cover in the same thickness as the main steel component. 

Existing buildings included

The increased heat input over the supporting steel panels needed to be taken into consideration where steel beams were to be covered regarding fire protection. This was the case at places where new intermediate ceilings in Holorib- style were created. For this purpose "Conlit"-panels were used in an insulation thickness that ensures one fire resistance class more than required.