Estonia’s highest office building, developed by Kapitel, has been tested in a wind tunnel in Germany
In order to ensure as human-friendly environment as possible and the highest possible quality of building structures, Kapitel ordered wind tunnel testing for its Liivalaia business and residential quarter development project. The tests conducted in Germany confirm that the structures and facades of the buildings are able to withstand the wind load of the strongest storm encountered in Estonia in the past 50 years. The study also provided additional information on how to avoid wind corridors around the building.
“In Estonia, the performance of such thorough wind analysis has not been required in designing buildings and, as far as we know, a similar study has only been conducted with regard to the Tornimäe high-rise buildings. The stability and safety of the building is a priority for us, and our aim is to create the best working environment, which also means ensuring a high-quality and human-friendly exterior environment. For this reason, we decided to take our project to Germany for wind tunnel testing as early as at the pre-design stage, so as to be able to take timely account of the obtained information in specifying the design solution,” Kapitel’s project manager Rait Riim explained.
“The test results show that the building structures and facades of the buildings in the Liivalaia Quarter are able to withstand the wind load of Estonia’s strongest storm of the past 50 years. In addition to the wind load on the structures and facades of the buildings, the analyses also focused on the natural frequency of the buildings as well as the prospective potential wind effect from future high-rise buildings in the vicinity of the Liivalaia quarter. In the near future, we shall also conduct an analysis of the internal wind corridors of the 111-metre office building, which is the highest in the quarter and the highest in Estonia, in order to avoid wind drafts inside the building,” Rait Riim added. “We have received confirmation that the entrances of the buildings have also been well planned with regard to winds, and the terraces planned for the roofs of the towers would be very pleasant places to be in summer. We also obtained valuable recommendations for designing the public square, pedestrian walkways and the Juhkentali Street bus stop pavilion intended to be built at the junction of Liivalaia and Juhkentali streets.”
In order to ensure the safety and comfort of the people working at and visiting the quarter, a model on the scale of 1:300 was made of the building in the course of the wind tunnel testing in Germany. The buildings were installed with 280 wind sensors and 36 wind directions were analysed. The reference wind strength was set on the basis of Estonia’s biggest storm of the past 50 years, where the 10-minute average wind speed was 21 m/s. With regard to assessing the comfort of people, the analysis covered an area with a radius of 300 metres as well as 40 most important places on the ground and on roof terraces.
The testing was performed by German company Wacker Ingenieure GmbH, which has performed wind related analyses for more than 2,000 projects in the past 25 years, including FIFA World Cup and Olympic stadiums, world-famous high-rise buildings and bridges.
“As of today, work on designing the quarter by Liivalaia Street has reached its peaks and we are hoping to obtain a building permit by autumn. We have assembled our design team purely of designers with the highest qualifications and the most extensive experience. As a result, we have remained on schedule and the design work so far has proceeded without major disruptions. The design process includes nearly 50 people, including consultants from England, Canada, Germany, Finland, Sweden, Denmark and Lithuania,” Rait Riim added. Kapitel’s investment in the development of the quarter is estimated to be EUR 100 million, construction works are scheduled to begin at the end of 2019 and the completion of the 1st stage is scheduled for 2022.
The Liivalaia Quarter, to be established opposite Hotel Olümpia, at the junction of Liivalaia and Juhkentali streets in the centre of Tallinn, will consist of three buildings: a 28-storey and 15-storey business building, a 9-storey residential building and a parking house connecting these. The highest building is planned to be 111 metres tall, which will make it the highest office building in Estonia and the fourth tallest building in Estonia after the Oleviste Church and the Tornimäe twin towers. The gross area of the Quarter is nearly 77,000 m² and lease area 36,000 m², including 28,000 m² of reputable class A office spaces and 3,000 m² of apartments, 5,000 m² of various catering and services areas. The developed buildings will be nearly zero energy buildings, with office spaces meeting the class A standard and the environmental sustainability being based on the international BREEAM standard. In addition to the new buildings, two new access roads will be built and, in cooperation with the local settlement association, a publicly used park is planned for the Härjapea River riverbed, as well as a public square style green zone beside the Church of Our Lady of Kazan.
Kapitel (www.kapitel.ee), previously known as E.L.L. Real Estate, is one of the Baltics’ largest real estate companies, and it been engaged in developing and managing retail, hotel and office buildings for more than 20 years. The group currently owns and manages over 185,000 m2 of leasable space. The company owns four office buildings (Delta Plaza and the Sõpruse Ärimaja office building in Tallinn, Narbuto 5 in Vilnius and I.P. Pavlova 5 in Prague) and various leading shopping centres (Spice and Spice Home in Riga, Panorama in Vilnius and about 30% of Viru Keskus in Tallinn). The company also owns the Nordic Hotel Forum (managed by OÜ Nordic Hotels) and, in joint ownership with AS Infortar, Tallink City Hotel (managed by Tallink Hotels).