INTERNATIONAL PROJECT
Student housing project inspires new heights
By Dovetail Communications Article first published in Wood Design & Building , 2020
Joensuu is a small but growing city – where more than 10 % of the population attends either the University of Eastern Finland or the Karelia University of Applied Sciences – student housing solutions are a priority .
Completed last year , the 14-storey Lighthouse Joensuu is Finland ’ s tallest wooden high-rise building , containing 117 student apartments and rising close to 165 ft . The city ’ s zoning plan specified that the site should utilise high-rise construction , favouring wood . As a result , the architects devised an all-wood plan ( beyond the concrete ground floor ) with innovative design features , including an exterior stone tile facade featuring a lightwork installation by Finnish ‘ light artist ’ Kari Kola .
The project ’ s goal was to minimise costs by using an efficient floor plan , optimised structures , and innovative technology . To that end , the ground floor and civil defence shelter – a standard requirement for occupied buildings over 12 917-sq . ft . ( 1 200m ²) in Finland – are made of concrete , but the remaining structure uses LVL floors and CLT walls , including for the elevator shaft . The structure is stiffened with numerous steel rods inside the wooden structures , tensioned from top to bottom .
The ground floor includes sauna facilities , a laundry room and adjacent drying room , technical facilities , and storage spaces for household and outdoor equipment . Floors one to 13 have nine apartments each , of which two are one-bedroom apartments and the remaining seven are studios , with the apartments varying in size from almost 280 sq . ft . to slightly more than 510 sq . ft .
Although the apartment building is made of wood , very few wooden surfaces are visible in the finished building ; most interior surfaces are clad with gypsum board to meet fire safety requirements . The fire safety design for the building is based on functional fire design , as the standard E1 tables only cover wood buildings up to eight storeys high . Sprinklers were installed throughout ( OH1 level , two-way water supply ), but the building was designed to withstand a fire even if the sprinklers do not work . Building regulations require third-party inspectors for both fire safety and structural design ; in addition , the ventilation systems were evaluated according to government standards .
Completed on schedule , each mass timber storey of Lighthouse Joensuu took less than two weeks to build . The panel blanks arrived at the construction site , where the window and door openings and the conduits for building services were then machined under the cover of a tent . The mass timber elements were then installed as the weather permitted . After installation , each completed storey was protected by a temporary roof to maintain the dry chain .
Lighthouse Joensuu ’ s wood components – almost 70 630 cu . ft . in total – store a quantity of carbon equivalent to the annual emissions of approximately 700 passenger cars . The Karelia University of Applied Sciences conducted measurements , acoustics research and evaluated the structure ’ s carbon footprint ; studies to-date reveal that only about one-fifth of the carbon footprint of Lighthouse Joensuu was generated during the construction period , and the remainder is operational , which is still under analysis .
The project – which won the 2019 Puupalkinto Wood Award and is nominated for this year ’ s International Award for Wood Architecture – was also supported by Finland ’ s Ministry of the Environment . As one of the tallest structures in the town , Lighthouse Joensuu illuminates the skyline at night and acts as a beacon – both for the town and for the future of wood construction .
Client Architect Wood engineering Wood supplier General contractor
Opiskelija-asunnot Oy Joensuun Elli Joensuu , Finland Arcadia Oy Arkkitehtitoimisto Joensuu , Finland Joensuu Juva Oy Joensuu , Finland A-Insinöörit Tampere , Finland Stora Enso Varkaus , Finland Rakennustoimisto Eero Reijonen Liperi , Finland
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