Metsätapiola, Espoo, Finland

Metsätapiola’s original office building in the “garden city” of Tapiola in Espoo was designed by the architect Erkki Virkkunen in 1973 and served its occupants well for decades. Space issues and out-dated technology have increasingly become problems in recent years, however, and plans were launched soon after the millennium for a new building, primarily for the company’s own staff. Architect Pekka Helin, well-known for numerous major e-h76bkqTkGVPJmsRujEeg across Greater Helsinki, was selected as the architect early on. “From the very start, we wanted to respect the original ‘close to nature’ idea underlying Tapiola,” explains Helin. “That’s why, for example, we gave the building’s façade along the area’s major local thoroughfare, Länsiväylä, strong verticals and varied detailing to act as a visual metaphor for a forest of tress. The exterior is particularly important with this building, as it will act as one of the signature landscapes for the entire area.” Laiho says Helin & Co. has had positive experiences with using Deltabeams in a number of other recent projects, including the recently opened Helsinki Music Centre. The Vahanen Group was responsible for the structural engineering of the latter, as it has been for the Metsätapiola building. “Deltabeams offer an indisputable package of benefits when you want low, load-bearing structures and frames with continuous beams and single-storey columns,” says Project Manager Matti Kannisto, who was responsible for the Metsätapiola project at Vahanen. “We were able to leverage these benefits even more because of the way the Peikko Group operates, which enabled us, as the lead structural engineer, to get all the design documentation for the Deltabeams and final dimensions in good time.” The fact that around 13,500 square metres of the building’s space is intended for the developer’s own use put particular emphasis on the need for a high standard of interior design, which was the responsibility of Helin & Co. “The office space of the new Metsätapiola building has been designed to be both modern and adaptable to different types of use,” says Mariitta Helineva of Helin & Co. “We’ve also given a lot of detailed attention to the materials used. It’s particularly important to plan where the Deltabeams end well, as this can free up a lot of interior height. Deltabeams are also easy to work with as an interior feature, as they can be left visible at ceiling level.” The positive previous experience that both the architects and the structural engineers had had with Deltabeams meant that the Peikko Finland was able to come on board at an early stage in the project. This was important, as it enabled the optimal dimensions for key parts of the structure to be agreed in line with the project’s overall budget early on. “We decided to use Deltabeams throughout the building, not just for the complex façade, giving us cleaner lines and overall design continuity,” says Antti Laiho. Second-stage concrete was poured on-site for the cantilevered sections of the façade and resulted in an integrated structure with the building’s Deltabeams. The cantilevered sections were tied into the hollow-core slabs using rebar reinforcement. The benefits of using Deltabeams also proved useful in solving the challenges associated with differences in slab height. “These are easier to deal with when you’re using Deltabeams, as the beams also act as forms for concrete work,” says Site Foreman Jari Salonen, from the constructor Haahtela-rakennuttaminen Oy. Working with Peikko Group was a positive experience overall, says Salonen. “They handled their responsibilities well. The Deltabeams beams arrived on site when they were supposed to and in the agreed volumes, typically one or two truckloads every two weeks. “You know things are going well when the supplier sticks to the agreed delivery times and everything fits just as it should do, in other words all the dimensions are just right. If I remember right, Peikko had just one manufacturing fault in its total delivery of 428 beams, which is a very low figure. And that one fault was corrected very quickly as well.” Works Manager Jari Pelkonen echoes Salonen’s views. “Peikko did a good job, in fact the whole project went well. It was very positive that we all had enough time to do our job well, as the developer had completed all the preparations for the project in good time. That’s certainly not always the case in construction today,” he says.