On our way from Stockholm to Oslo we passed a gigantic paper factory somewhere in Sweden. Big piles of trees were waiting to be made into paper. That is what happens to most trees in the Swedish wood industry. Sweden has however a long tradition of building in wood. Wood frame building has been the main building technique for centuries. Nowadays Sweden builds mostly in concrete. This development started already before the so called Millionprogram that the Swedish state has initiated in the 60’s to fulfill the enormous postwar housing demand.
But the Millionprogram certainly has given concrete building an enormous boost. Today the Swedish building industry is dominated by ‘the big four’, building companies who all build mainly in concrete and who take care of the majority of the total building production in Sweden.
To us it is very surprising that a country with so many trees and such high environmental aims doesn’t build more in wood.
There are however some small countermovements. The municipality of Växjö for instance promotes building in wood. They call themselves the wooden city (http://www.vaxjo.se/trastaden/). Midroc Property Development has built Limnologen, an eight stories housing block, which was at that time, in 2009, Sweden’s highest building in wood.
Växjö municipality challenged Midroc by offering them the possibility to double the building volume if Midroc would build in wood. Midroc hired Architect Bolaget, a local architect who was already experienced with building in wood. They cooperated with a manufacturer, specialized in wood construction. They succeeded in building an eight story building that fulfills all the regular technical requirements. Apart from a few extra measurements in concrete and steel that were necessary to make the building more heavy and to tackle windforces, the whole construction is made of cross laminated timber, also the elevator shafts.
Calculations of Folkhem, a municipal housing company from Stockholm, point out that building in massive wood is now around 15-20% more expensive than building in concrete, but a reduction of building time has not been taken into account. Midroc has however realized the project for a regular budget because they also operated as main contractor. The reason for this was not to cut costs but because no contractor was willing to take the risk for such an experimental project. The framework of the building was built by Martinsons Byggsystem, the manufacturer of the wooden construction elements. For the other part Midroc hired a small local contractor.
Production of wood construction is not at all optimized in Sweden. The capacity of factories is not used to its fullest potential. Building more in massive wood would definitely lead to lower costs and lower risks. On top of that, building in concrete is not at all as industrial as it used to be in the postwar era, according to Erik Stenberg, who researches the postwar housing period at the KTH. The environmental specialist from one of the big four construction companies has supposedly stated that they produce 2,5 tons of waste for each apartment. Industrialized building methods have been replaced by low payed workers who build on the site.
We have been told that Folkhem Is going to build only in wood. That sounds like a brave and ambitious statement in the Swedish context. They have recently finished their first wooden highrise building in Stockholm after the design of Wingård Arkitektkontor in the area of Sundbyberg.
Also Anders Persson of Midroc states they are working on more buildings in wood. So there are some good signs, but still the question is if also the powerful concrete builders will seriously develop other, more sustainable ways of building.