Translation of an article published in Tekniikka & Talous, 3.10.2014. Original article written by Eeva Törmänen.
Wood construction is increasing in Finland but there are very few developers
The development of wood apartment buildings is relying more on Stora Enso than before. “There are currently only two active companies in developing the construction of wood apartment buildings: ourselves and Rakennusliike Reponen,” says Matti Mikkola, Vice President, Building Solutions, Stora Enso Building and Living.
Other wood apartment building developers have been passive in their building projects in recent years.
“Versowood built an apartment building in Vierumäki together with Reponen but since then they have not built anything. Finnforest has its own system but they too have not been very active recently,” says Mikkola.
Ari Tiukkanen, Senior Vice President, Building and Industry, Metsä Wood, admits that the company, formerly called Finnforest, is currently not involved in any wood apartment building project that is under construction.
“We have projects in the development stage but not under implementation,” he says.
Among other projects, Metsä Wood is involved in the block of wood apartment buildings planned in Tapiola, Espoo, where Asuntosäätiö is the developer. The project is in the planning stage and construction will probably begin in 2016.
“There also some commercial projects but I don’t know how public they are.”
Tiukkanen wants to differentiate between product component supplies and the supply of massive CLT elements.
“Supplying massive CLT element is a really big entity for a wood component supplier, as is the liability involved. This is not our strategy. Our aggregate delivery has to remain with just the wood, we don’t want to take on the liability that a construction company has to the consumer. We are happy to take on the liabilities of a component supplier.”
Although Tiukkanen views the manufacturing of massive CLT elements as being almost the same as construction, Stora Enso emphasizes that the massive CLT elements are also part of the component supply.
The company is currently implementing a project consisting of four wood apartment buildings in Helsinki together with SRV. Stora Enso is supplying the massive CLT elements for the houses and SRV operates the actual building site. The buildings will have a total of 93 rented and right-of-occupancy homes.
Stora Enso’s next cooperation project with SRV is the wood apartment block planned in Jätkäsaari, Helsinki, where construction is due to start next spring. Stora Enso is also supplying massive CLT elements for the BoKlok small apartment buildings constructed by Skanska.
The share of wood is rising
At the moment, wood apartment buildings make up about 3-4 per cent of new apartment buildings. Around the world the volume of wood apartment building construction can be surprisingly high. In the United States, 90 per cent of new-build residential apartments are made from wood, in Scotland 70 per cent, in Japan 55 per cent, and in Sweden 20 per cent.
The wood is not always visible on the surface. For example, in Scotland the facades are laid with bricks or plastered, whereas in the United States fibre cement and vinyl boards are used.
In many countries there is a long tradition of constructing wood apartment buildings. For example, in the United States there is a lot of affordable labour and the houses are built of wood on location.
“The most common construction method is always the cheapest. When some construction method becomes more popular, the development investments also accumulate there,” says Mikko Viljakainen, Managing Director at Puuinfo.
“It is said that if you reach a market share of 20 per cent, then the market starts to pull itself.”
However, Stora Enso cannot support the production of wood apartment buildings on its own, despite having a big manufacturing system and the company’s backing behind it.
“Our hope is of course that other suppliers will also come in. Otherwise the growth will not continue,” says Mikkola.
In the future the massive CLT element might be a certified and licensed product that will also be sold for others to manufacture.
But how much CLT construction is required before Stora Enso will build its own CLT factory in Finland? Currently the CLT boards for wood apartment buildings are imported from Austria.
“We are beginning to reach that point,” promises Mikkola.
Stora Enso has been developing the construction of wood apartment buildings and use of CLT boards for five years. A few years ago its factory in Pälkäne was still producing large CLT elements but now the production is mainly geared towards the massive CLT elements.
The advantage of the massive CLT element is the speed of construction it enables and the dry factory production conditions. Its weakness is the impossibility of making changes. Since the elements are finished at the factory all the way to the interior surfaces, the home buyer cannot any more make the decision about the floor material or the bathroom tiles of an apartment at the construction stage.
It’s not possible to get into the mood of wood in the wood apartment buildings. Due to fire regulations, all the wooden CLT surfaces must be covered behind plasterboard and panels.
“According to the regulations, no wooden surface can be left visible at all but with the help of functional fire design the wooden surface of the ceiling, for example, can be left visible,” says Janne Manninen, Director, Sales & Projects, Stora Enso Building and Living.
The CLT surface is also not visible on the building exterior.
“CLT is not type-approved but in theory it is possible. Even logs are used for exterior walls.”