Stora CLT spans the world

Stora Enso is a top 10 Swedish sawn softwood producers, which makes it one of the biggest producers worldwide.

Recent years, however, have seen the company add another significant string to its bow; the manufacture of CLT and supply of prefabricated panels.

In fact, with two bespoke CLT mills in Austria, Stora Enso now has production capacity of 120-160,000m³ annually, making it one of the biggest manufacturers globally.

And since supplying the structural CLT panels for nine-storey Bridport House in London, it has become one of the leading providers to the UK.

With CLT increasingly being specified for the whole range of building types from education and healthcare, to low to medium-rise residential, the company is seeing a clear development path for its European business from individual wood products to building solutions. In particular, it expects its level of international activity to grow in the residential sector.

European Projects
Working through a partner network, Stora Enso is active throughout central Europe where it is delivering small and medium-sized projects ranging from high-end residential projects to kindergartens, schools and hotels.

The diversity of the different European markets is a key factor shaping the company's CLT strategy.

"The customers' needs are different across Europe, and we're adjusting our offer accordingly to ensure that they're fully met," said Matti Mikkola, head of building solutions at Stora Enso Building and Living. "For example, in Finland, where we have volumetric production capacity for 1,400 modules at two production sites, our offering is based on the volumetric elements including internal and external fittings and M&E, as well as on-site installation."

Several residential multi-storey projects are under way in Finland, which will see a total of approximately 250 apartments completed in 2014, and in Helsinki Stora Enso's Wood City, billed as a "masterpiece of wooden construction", comprising an office development, hotel and apartment buildings, starts work this autumn.

In the UK, where the focus is mainly on the residential and educational sectors, Stora Enso works with construction partner Eurban, a specialist in large and multi-storey projects.

"The CLT market is developing well in the UK and the projects are getting larger and more demanding," said Mr Mikkola. "But we're ready to meet the challenge in supply and technical support."

Fire Test Report
Stora Enso recently published the first CLT-specific fire test report in the UK, commissioned to ensure that accurate, up-todate fire safety data is available to customers.

"It's essential to our strategy that specifiers can easily get answers to technical questions at this level," said Mr Mikkola, adding that the company's CLT system is designed to boost the efficiency of the entire construction process.

"And our ambition is to further develop the wood-based construction methods in key markets," he said.

Those key markets are now spreading increasingly globally and the wood-based methods becoming increasingly diverse.

In the UK, among the latest projects Stora Enso has been involved with is the redevelopment of an agricultural building at Shatwell Farm in Somerset, to provide an architectural archive and office. Two new CLT structures have been built within the original stone and brick walls of the barn.

Both rooms have underfloor heating powered by an air source heat pump and there is a wood-burning stove for very cold days. The CLT construction is not insulated, externally clad or internally lined, yet provides a stable internal environment for the archive.

In Italy, Stora Enso CLT has been used for the superstructure of the recently completed Via Cenni in Milan, currently the largest timber construction project in Europe.

The project comprises 124 social housing apartments set in four nine-storey buildings, each 27m high. Among the factors behind CLT's specification were its ability to perform well in earthquakes. Speed of construction was also important, with the project completed in approximately 12 months.

Further projects
In another project in the urban development district of Barmbek in Hamburg, 11 families have created a shared living space in a disused goods yard. Among the residents is Neil Winstanley, one of the building's designers at Spine Architects.

The homes are built in three separate buildings, using 120mm CLT elements which were prefabricated in the Stora Enso unit in Ybbs an der Donau and then assembled on site. Using CLT effectively reduced costs because of the material's speed and ease of installation - the project, comprising 540m³ of CLT was completed in 13 months.

In Austria Stora Enso has been involved in a multi-storey Passivhaus level project, while in France "partner co-operations" are set to start large developments this autumn.

The company is also developing a supply pipeline to serve the growing Australian market. This follows successful completion of another impressive, large-scale CLT project, the Docklands Library & Community Centre at Melbourne's Victoria Harbour.