Hamburger Börs
Hamburger Börs, a landmark in the centre of Turku, underwent a careful and controlled renovation
There are not many landmarks in the centre of Turku that are as valuable and beloved by the city’s residents as Hamburger Börs, which has stood on the edge of the Market Square since 1885. The structural engineering of this renovated Scandic hotel relied on cost-effective and reasonably feasible solutions.
The official name of Hamburger Börs has changed over the decades, and there have been many different types of hotels and restaurants on the site. In the 1970s, the original Art Nouveau hotel building was demolished and replaced by a new one built by SOK. The oldest part, completed in 1885, is protected. Börs has been owned by LocalTapiola since 1979.
In 2018, the hotel’s history gained a new chapter when parts of the old Börs were demolished, the oldest part was renovated and an additional wing was built. In addition to more than 270 rooms, the 10-storey hotel includes restaurants and business premises, a multistorey car park and a rooftop bar located on the ninth floor above the ventilation machine room. The high-profile project was implemented as a YIT project management contract, for which a familiar partner was selected to carry out the implementation planning.
“Working with the Sweco team has always gone well, without any need to fight over schedules or additional work invoices,” says Juha Kohonen, Project Development Manager at YIT Finland Ltd. According to him, Sweco’s structural engineers always offer a good set of options. “Once again, Sweco gave us some solid initial ideas that were good to build on.”
The new Börs was built on existing piles
From the outset, it was known that the location of the site would be challenging. Eerikinkatu had heavy traffic during the construction phase, and the area around the old Börs with its deciduous trees had to be carefully protected. Space on the site was limited, and the clay soil made foundation conditions difficult. Aki Luntamo, Department Manager for Structural Engineering at Sweco, says that it would have been unwise to try anything too new and uncertain on a site like Börs. “We made use of proven and reasonably feasible solutions.”
The largest cost savings came from the frame solution for the new building. At Sweco’s suggestion, the frame was constructed with concrete elements with a column and beam structure. “Originally, the frame was designed as a steel structure, which would have been a much more expensive option,” says Kohonen. The solution worked, even though the load-bearing lines could not be implemented in a completely straightforward manner and exceptional solutions were needed for the concrete walls between the suites.
The old wing on Eerikinkatu was demolished down to its foundation to make way for the new building. Time, money and materials were saved by being able to erect the new building on top of the old piles. “Of course, the piles were not positioned optimally, so the loads of the new frame were transferred to the foundation through a thick base floor slab,” says Luntamo.
The pitched sheet metal roof was implemented with prefabricated elements
Looking at Börs’s facade, the eye is drawn to the beautiful pitched roof. The wooden roof elements underneath were prefabricated at YIT’s factory. This allowed the building to be protected from the weather in just four days. The element design of the pitched roof was carried out with the help of Sweco’s experts in wooden roof structures. Kohonen saw this as a huge bonus. “It all went very well and saved us time and money.”
In the renovation of the old Börs, the trickiest challenge were the steel structures of the existing terrace. The old terrace was dismantled and stored for the duration of the renovation, but in the process the old steel parts proved to be so worn out that they were no longer safe to use. “This led us to design new load-bearing steel structures for the terrace based on the old ones,” says Luntamo. “The end result looks so good that not many people would guess that the structures are new.”
It now warms his heart to walk past the renovated Börs and see the finished result. Even the most critical members of his own family have praised the site. “Börs is such a major and well-known landmark in Turku that even my wife and daughters appreciate this project!”