Finland’s largest wooden multi-storey building completed

Finland’s largest wooden multi-storey building to date, comprising 104 flats, has been completed in Viikki, Helsinki. Based on the Metsä Wood Multi-Storey System, the block is composed of five wooden buildings, each with three to four floors, with a total gross floor area of 6,300 m2. The first residents took occupancy in June, and now all of the premises are ready to move in to.

“The project proved that wood is an excellent alternative for industrial construction of multi-storey buildings. Many of the traditional challenges associated with the construction of wooden multi-storey buildings were solved. The residences in Viikki are state of the art in terms of fire safety, soundproofing, and energy-efficiency,” says Ari Tiukkanen, Senior Vice President Building Products, Metsä Wood.  

Plenty of new information and research results were collected and obtained during the construction. While the project was in progress, VTT Expert Services Ltd carried out a carbon footprint assessment, among other measurements, for the site. Tampere University of Technology assessed the building’s air-tightness, and Helimäki Acoustics carried out acoustic measurements.

The housing is equipped with an automatic fire-extinguishing system, which gives an unsurpassed advantage when compared with the fire safety of the traditional construction method: in the event of a fire, the automatic system prevents the fire from spreading, the temperature will not rise, and there will not be a decrease in the level of oxygen in the room. If the system is activated, the amount of water needed is very small, thanks to the spray technology used (1.4 l/min). This prevents any significant water damage. 

The Metsä Wood Multi-Storey System comprises a Kerto-structured beam-and-post frame, intermediate floors, roofing panels, and exterior walls delivered as timber frames. The balcony structures and awnings of the houses were created with Kerto and glulam elements. The impressive 42-millimetre-thick King Panel, made from Metsä Wood’s King Beam glulam, crowns the wooden multi-storey buildings. A façade panel that is up to 12 metres long creates a harmonious and clear line for the housing.

The Metsä Wood Multi-Storey System fosters cost-effective construction of multi-storey buildings, because it significantly reduces the construction time needed, decreases on-site labour, and minimises loss of materials.
“The frame and intermediate floor phase in Viikki was accomplished very quickly, because no drying related to concrete construction was needed and construction work could continue without delay. Viikki also taught us how the construction process can be improved further,” says Tiukkanen. Construction began with foundation work in the summer of 2011.

The Metsä Wood Multi-Storey System has been developed over several years through a network of leading experts in the construction industry, and the system has been used in the construction of wooden multi-storey buildings in a number of countries including Germany, France, and Italy. Finnish developers have also expressed a keen interest in wood-based construction, with almost a dozen new areas of wooden multi-storey buildings being planned, in locations all over Finland, including Espoo, Turku, Rauma, Tampere, and Ylivieska. 


Carbon footprint 45 per cent smaller than that of a concrete building

The energy used in, and carbon footprint of, construction of one wooden multi-storey building was calculated in assessments carried out in Viikki. These calculations included the building’s life-cycle carbon footprint over 100 years. Results were compared with those for an equivalent new concrete multi-storey building, and the carbon footprint of a wooden multi-storey building (347 t CO2 equiv.) is 45 per cent smaller than that of a concrete building. 

The energy required for production of materials for a wooden multi-storey building was 4 per cent less than that for material production for a similar concrete building. During a hundred-year life cycle, heating energy will make the most significant contribution to the carbon footprint, accounting for more than 80 per cent of the total carbon footprint. The carbon footprint of one wooden multi-storey building over 100 years is 3,928 t CO2 equiv. and energy consumption 63.2 TJ, including the energy used in material production, transport, repairs, operations on the site, and heating. 

The results of air-tightness and acoustic measurements are also excellent and clearly meet – and surpass – the requirements of current building regulations.


Etera Mutual Pension Insurance Company is the construction manager for this project, which is part of the City of Helsinki's Developing Multi-storey Building programme, and the main contractor is Peab Oy.


Images of the site can be downloaded from Metsä Group’s image bank:
http://databank.metsagroup.com/?cart=826-efaclbemjj&l=FI


Source of more information:
Ari Tiukkanen, Senior Vice President, Building Products, Metsä Wood  tel. +358 50 598 7293
Olga van Iterson, Marketing and Communications Manager, Metsä Wood, at tel. +358 50 325 2376 


www.metsagroup.fi 

Metsä Group is a responsible forest-industry group whose products are part of people’s everyday life and promote sustainable well-being. The business group produces high-quality products mainly from renewable Nordic wood and wood fibre. Its areas of business are tissue and cooking papers, board and paper, pulp, wood products, and wood supply. Metsä Group’s sales totalled 5.3 billion euros in 2011, and the group employs approximately 12,500 people. It is present in some 30 countries.

www.metsawood.fi

Metsä Wood offers competitive and eco-efficient wood-based solutions for industrial construction customers, other industrial customers, and home and lifestyle sectors. We manufacture products from Nordic wood, a sustainable raw material of premium quality. Our turnover was 940 million euros in 2011, and we employ about 2,900 people. Metsä Wood is part of Metsä Group.