The Builder’s Rose, an annual award issued by the Helsinki Construction Committee, is an acknowledgement of exceptionally high-quality work related to the built environment. This year, the Roses went to OP’s new office building in Vallila and the Meripaviljonki in Hakaniemi. The awards, presented in January, were given out for the 21st time.
The developments rewarded with the Rose in 2016 represent the currently in-vogue field of complementary building. According to the jury of the Helsinki Construction Committee, the Meripaviljonki is a praiseworthy expression of Helsinki’s maritime policy. The restaurant enriches the historically valuable urban landscape of Siltasaari and echoes the round shape of the Ympyrätalo. The building is in line with the City of Helsinki’s goal of increasing the use of its waterfront areas. The challenging idiom of the building’s facade has resulted in a generous amount of detail to which the designer and developers applied themselves with fantastic results. The design and implementation of the technically unique development also required daring and creativity from all parties involved.
Long-awaited and meticulously designed
Restaurant Meripaviljonki, floating in Eläintarha Bay, is one of those architecturally impressive developments that justify the phrase “good things come to those who wait”.
The Workers’ Association of Helsinki started planning for a floating restaurant in Siltasaari nearly two decades ago. The decision was politically difficult and was only settled in the courts in 2008. The challenging geotechnical engineering process for the Meripaviljonki was accordingly started by Fundatec Ltd in 2009, and the company was later merged with Sito. Specialists such as Geotechnical Engineer Jarmo Rajaniemi drew up the designs under the direction of Senior Consultant Aku Varsamäki.
For a Finnish restaurant building, the Meripaviljonki is exceptional. Even though the building almost touches the shoreline, it is completely free-floating, anchored to the bottom by beams. Jarmo Rajaniemi describes the frame as two ships floated to the site and tethered to each other on location. The floor area of the Meripaviljonki is 400 m2, the restaurant weighs approximately 400 tons, and the building’s bottom lies approximately 2.5 m below the surface. The roughly 100-square-meter technical facilities, such as the switchboard, air supply unit room, sewage pumping station and heat distribution room are all located inside the frame.
The restaurant is connected to the city’s district heating, water and sewer systems and to the electricity grid.
Fascinating design project
This exceptional restaurant building’s geotechnical engineering design process was also extraordinary. Transportation routes had to be mapped for the structures, which entailed sounding the bottom and investigation of the bridge opening. For the dredging plan, the engineers had to determine how polluted the bottom sediment was, and the management of these surveys were a part of the bottom structure design process.
When a project drags on, there are more opportunities to make changes. The building’s frame was changed from concrete to steel in the course of the design process, which naturally changed the dredging requirements as well.
Sito’s duties also included designing the support type for the shore structures, along with the structures of the floating restaurant’s anchoring points. “There were several alternatives for anchoring the original structure. Originally, the plan was to anchor the structure with chains at six points. In order to minimize the building’s movement, however, we finally opted for two pile beams to which the Meripaviljonki was tethered with steel beams. This option allowed for vertical movement and slight bobbing. If we had used the chains, the restaurant would be moving in all directions,” says Jarmo Rajaniemi.
According to Rajaniemi, one option was to embed sufficiently rigid bored piles straight into the rock at an angle. This would only have permitted vertical movement, however. “We thought that the building should bob gently on the waves,” Jarmo Rajaniemi recalls.
It builds atmosphere in a marine restaurant!
Architects Freese Oy were responsible for the architectural design of the Meripaviljonki, with Europlan Engineering Ltd acting as the main contractor.
Text: Dakota Lavento