Analysis shows deficiencies in Mitte station and Mathildenschule
20.06.2025 – The demolition work inside the Mitte station continues to progress. The same applies to preparations for the comprehensive renovation of the first of two existing parts of the Mathildenschule from the 1970s, after the new building for the integrated comprehensive school was completed in July 2024 and is now in operation.
Analyses by OPG, the public utility company commissioned with the conversion, and the deficiencies identified in the process, whether in the fire protection of the ceilings in the former Kaufhof building or in the building fabric of the first of two existing parts of the Mathildenschule, now enable careful, more reliable and adjusted time and cost planning for both construction measures. In the case of the Mitte station, the fire protection properties of the ceilings require an extension of the ongoing Europe-wide tendering process for a general contractor.
Center station
The Stadtwerke subsidiary OPG Offenbacher Projektentwicklungsgesellschaft mbH is currently working on behalf of Station Mitte GmbH on the preparation of the building application documents and specialist planning for the technical building equipment, which should be completed by the summer vacations, and the demolition and dismantling work is also continuing as planned.
In the course of the current demolition and dismantling of the old technical installations inside the former department store building, the condition of the ceilings in particular has been examined in recent weeks. Comprehensive structural investigations, including concrete sampling, were originally planned for the spring. However, due to resource bottlenecks at the company initially commissioned, there were delays and the order had to be canceled. A new specialist company has now been commissioned to carry out the necessary investigations. These are currently still underway and will also serve as the basis for the fire safety assessment of the building fabric by an external expert. However, and this is a new finding that the public should be informed about at an early stage: Initial preliminary results indicate that the older part of the building in particular is unlikely to meet current structural fire safety standards without further measures.
Boris Kupke, Managing Director of the Stadtwerke's Geschäftsfeld Immobilien divisionIn the case of construction projects in existing buildings, it is often the case that detailed knowledge is only gained during the demolition work. The initial assessments now available from the fire protection expert indicate a specific need for action. We are currently developing suitable solutions - including targeted compensation measures such as upgrading the existing sprinkler system, parts of which have already been replaced by the previous owner.
Unfortunately, it must be emphasized in all clarity that additional time will be required for a reliable technical and economic evaluation of these options, coordination with the experts and integration of the results into the ongoing award procedure. "Furthermore, and this is also important to state openly, it is quite likely that the necessary measures will lead to higher overall costs," Boris Kupke continues. "This is why we cannot award the contract as quickly as originally planned."
Andreas Herzog, Managing Director of Station Mitte GmbH, adds: "With these new findings, which have emerged as part of the dismantling measures and investigations, we will no longer be able to award the contract to a general contractor in summer 2025 as originally planned. We don't expect this to happen until the end of the year". The postponement means a delay in the project of around six months.
"The previous very tight project schedule was based on the assumption that there would be no negative surprises, as was the capped project cost plan for the issues known to date. In the course of in-depth investigations, there is now a high probability that more adjustments will need to be made to fire protection," says City Treasurer Martin Wilhelm, who is also Chairman of the Supervisory Board of Station Mitte GmbH. "Even if we would like it to be quicker, under these conditions cost-effectiveness comes before speed. In principle, it would be possible to award the contract quickly within the original schedule. However, it would very likely cause subsequent cost increases in the course of the project. This would increase our financial risk. I don't want to be responsible for such an approach," says the city treasurer. "We therefore want to maintain the competitive situation for the changed fire protection requirements by not awarding the contract now in order to achieve the most economical result for the city. On the one hand, it would be premature to specify higher costs because this would take the pressure off the competitors. On the other hand, it should be clear to everyone that higher overall costs are now obvious. In order to keep them within reasonable limits, we are now taking the time to assess the fire protection requirements in detail," says Martin Wilhelm.
Mathilden School
A similar problem with regard to fire protection can also be seen at the Mathildenschule, where the first of two existing buildings is currently being completely renovated. In a first step, the entire suspended ceilings in this part of the building were dismantled. As pollutants can be released when removing the suspended ceilings, it was not possible to open up large areas of the building during the planning phase. "There was no danger from the suspended ceilings as long as they were permanently installed as in the previous school," assures Oliver Frey, Head of Building Construction in the Stadtwerke's Geschäftsfeld Immobilien division.
The reinforced concrete structure is now completely exposed. After extensive investigations, it was also found that the columns and ceilings at the Mathildenschule do not meet today's fire protection requirements. In contrast to the Mitte station, where the existing sprinkler system can be integrated into the solution, other approaches need to be investigated at the Mathildenschule.
Furthermore, it is now apparent that the reinforced concrete structure needs to be extensively renovated in order to ensure that it continues to function safely in the long term. On the one hand, this requires the refurbishment of reinforced concrete components and supports where concrete has flaked off over time. On the other hand, existing steel connections between the reinforced concrete parts must be additionally secured. These defects were already caused during construction in the 1970s, but have only now been uncovered in the course of the uncovered supporting structure.
As not all final investigation results are available yet, costs in the mid single-digit million range for fire protection and the refurbishment of the reinforced concrete structure are calculated for the component undergoing refurbishment and for the subsequent component.
In order to achieve a higher level of planning certainty for the next part of the building, there will be an extensive inspection of the next part of the building during the summer vacation. Due to the contaminated suspended ceilings also installed there, these investigations will take place in correspondingly elaborately cordoned-off safety areas. The planners are reducing the scheduling risk with this investigation. The planners are assuming a construction time extension of at least 3 months for the component currently being renovated alone.
