This piece was originally written in the aftermath of a visit to Finland and Sweden in during february 2002. It explores the Finnish wood culture, and the ideas of a how the Nordic forests could provide the basis of a pan-European timberbuild culture. Although never published, and in part a travelogue diary of the visit, it formed the basis for the Timberland Renaissance for Europe piece in Fourth Door Review 6 OL Feb 2009
In Finland the Boreal forest never lets up. This country of softwood and lakes – principally pine and spruce, plus a hardy regional birch – is an endless sea of dark conifer green, up in the northerly latitudes where agriculture hasn’t found its usual footing, and where the trees haven’t given ground to clearings. Three quarters of the country is dense forest – 23 million hectares – the largest forested area in all of European Union Europe.
Finland is also home to one of the world’s most respected architectural traditions, an architect’s architecture, which has maintained a pole position since the country’s best known architect Alvar Aalto brought a regionalist Finnish modernism to international attention in the 1940’s and 50’s. More recently the country has seen the sky-rocketing growth of a burgeoning new media and telecommunications industry, led by the mobile phone giant, Nokia. Nokia is propelling an image of this small Baltic country into the world arena as completely modern, and networked; a laboratory for the future.
If this futurism lived up to its image, all the ingredients ought to be there for a dynamic forward-looking approach to a sustainable building culture; wood: the largest resource of renewable material on the continent; a building and architectural tradition renowned around the world; and a new media culture which, you might imagine, could be harnessed both for designing a timberbuild futurism, and supporting the r & d for new technological tools to apply – in sustainably sensitive ways. Indeed you might have thought that the natural preponderance of wood – a quick calculation, tripling the estimated 2.2 billion cubic tonnes suggests 7 billion trees – would have precipitated a thriving timberbuild industry sensitive and responsive to environmental issues. It doesn’t seem far fetched to assume that a culture, which has grown up with, and literally within, forests, and with an enviable architectural reputation, would be receptive to, and pro-active in addressing sustainability issues in its building programme, and that timber the sustainable material par excellence would be the centrepiece – But sadly this isn’t the case. In Finland – as with the other Nordic countries, even if timber is a central and cherished tradition, in the last hundred years it has become marginalised in favour of, concrete, brick and latterly steel. have become the second nature materials. And Shockingly, during the last three decades, many aspects of the timber building tradition have almost disappeared.
Today, however, there is a resurgence of interest in wood amongst the Finnish building and architectural community, accompanied by some realisation of what has been lost, and by growing awareness of – the environmental benefits explicit in the country’s largest resource. A wide variety of projects have recently been funded, showcasing some of the most ambitious Nordic woodbuild ventures for decades. At the same time regulatory change, particularly to fire codes in 1997, have enabled the design and construction of buildings, and in places, hitherto all but inconceivable. All through this in the domestic market, individual builders have shown that in smaller-scale building, wood has manifestly maintained its appeal. Single storey homes and second homes, as well as the ubiquitous sauna, are a burgeoning and assumed part of the timber industry. In fact, as Helsinki Technical University’s Georg Grotenfelt: the Nordic countries’, and maybe the planet’s, first professor of wooden architecture says, small second homes have been a principal site of wooden design experimentation by architects, which includes Grotenfelt’s own respected designs. The figures for single storey buildings are reassuring set against the single percentage figures of larger building types. 90% of single storey, and half semi-detached buildings are wood based. But these high levels decline raplidly to, for instance, a paltry 3% for multi-storey and 2% for office buildings. Similar low figures are found with other larger non-residential building types. Whereas there are a wide variety of single-family housing, kindergartens, schools, sport halls, pavilions, and the like being built, other building types, such as corporate offices and public, educational and municipal buildings, which make up the vast majority of buildings are far and few between. Despite the changes the pointed fact is that, at present, Finnish architects have had mainly to head south to find out about the ground-breaking innovations in timber building. Any vision of wood as the source for a dynamic and sustainable building culture, despite its abundance, has so far manifestly failed to take hold in Finland.
The apparent indifference is partially historical. The Finns perceive themselves as a forest people, in their hearts at least, with long timber building traditions, even in large, completely timber urban areas “ but the material has been in retreat for over a hundred and fifty years.
During the nineteenth century many of the country’s large cities, including Eastern Finland’s Turku, were wood cities. But in the mid-nineteenth century the age-old problem of the material’s inherent combustibility came home to roost. Huge and destructive fires repeatedly raged through large and small towns alike. In 1827 half of Turku burnt down; 2500 buildings were consumed in the blaze. As a result, stone began to replace wood as the building material of choice, becoming the preferred, and before long predominant material. Timber towns, timber cities went into eclipse, and today, travelling through these Finnish cities, one can pick out only the outline husks of these former timber built communities: clumped single and double storey houses lost in the cities’ modernist 60’s grid remake.
Overall, the timber heritage is hard to track down. Unlike Norway, where up to 300 hundred medieval buildings are still standing, Finland’s innumerable wars and invasions – sitting between the two historically larger Russian and Swedish powers – meant troops invariably used building wood as fire fuel for the cold, winter nights. The consequence is a complete absence of any medieval wood buildings in the country. Ironically it was just as the larger towns abandoned timber as their primary building material that industrial forestry really began. The usual dating is 1864, when legal restrictions on steam-powered mills were lifted. Prior to this the mills had been water powered, located at the mouths of the big south flowing rivers into the Baltic, or watersheds between the vast network of rivers and lakes in the south and east of the country.
After world war two, war-torn Finland embarked on a huge building programme to house its increasing urban population. The influence on the country of bordering the erstwhile USSR weighed heavily during these years, its independence compromised by needing to watch its step or face the possibility of being taken over by its powerful neighbour. As a result Finland’s cultural links to both Nordic, as well as middle-European influences wasn’t as close as might be assumed. This may account in part for the brutalist approach to urban planning of the post-war era, and the rise of many concrete cities across the country, although neighbouring Scandinavia proper has just as much a tradition for unappetising sixties’ flat blocks, described by one as ‘Stalinist baroque’. Wholesale demolition of many major cities’ timber heritage paved the way for concrete and steel mid-rise; a functionalist approach which presently dominates the Finnish cityscape. This new generation of building stock brought significantly better living conditions inside, but their external features have not aged well. There are exceptions of course, but when I was travelling round Finland during winter, these concrete box buildings, merging with the murk-heavy grey of an average day, appeared far from inspiring. In turn, in the thirty years or since, the industries which grew from this massive reconstruction, and the orthodoxies that became accepted thinking, have remained in place, eager to defend business advantages, and ill-at-ease with new thinking and changed circumstances. In all these competitor sectors with vast investment, skills, and machinery embedded in the concrete, brick, steel and glass it isn’t surprising that these industries are intent on maintaining their hold on the building market.
Logically, the proposition that timber is one of the best sustainable options available stacks up well. Primary figures have been rehearsed often enough but, once again, energy used to produce wood is minimal compared to other modern materials; a quarter the amount of energy is required for concrete, and many times less than for the other primary competitors, brick, steel, aluminium and plastics. Forests are also carbon sinks in the post-Kyoto world, and carbon can be locked into the buildings for centuries. Not only this but their lightness is also significant; timber buildings weigh only one fifth of their concrete competitors. In Finland, however, these kinds of sustainable arguments are only beginning to leak into the equation, and then with hardly the dynamism they are associated with in certain EU countries, Germany for instance. At the same time the skills base which had maintained much of the timber tradition up until the sixties found few outlets for its uses, and began to dry up.
Another more contemporary reason for the dearth of timber building in recent decades, particularly since the take-off of Globalisation, has been the structure of the large Finnish wood companies. FinnForest, United Paper Mills and others hold some of the largest saw, paper and pulp mills on the planet, a multi-million Euro-industry making Finland a leading player in transnational industrial forestry. Critics repeatedly argue that the vertical integration of these companies, with their concentration on pulp and paper, has meant smaller companies have been forced out of the timber market. Even if pulp and paper are generally cited as the primary culprits, one might ask whether cutting trees down at such a massive rate is actually such a good idea. After all, the Finnish forest is itself part of the Boreal forest and the planet’s longest natural border, stretching from Siberia to Norway and on across North America, creating a northerly green halo around the world, described by some as the planet’s green lungs. There are passionate forest activists fighting to maintain what old growth remains in this huge area, and to develop legally recognised forest industry standards. There are old-growth forests in Finland (about 3.5% of the total remains,) mainly running along the border rim into Western Russia in the east and North-East of the country. But for the most part the forests have been long managed, in ways which, historically, have been questionable from the perspective of many forest activists. If you talk to people in the timber world, and also to a certain extent the forest activists there is a varying degree of acknowledgment in both camps that many of these companies have cleaned up their act.
It is an environmental paradox often ignored by many of the players, that in others concerned with planet sustainability see timber-based building as a crucial key to a forward looking low-energy building culture. But this means bringing the trees down. Architects and builders don’t generally have the same priorities as forest activists, and despite shared aims, there are knotty differences. The Nordic forests, with their fast growing intensively managed secondary woods epitomise this dilemma, since many in the Nordic sustainable architectural community appear to support the timber companies’ attempts to increase the timberbuild share of the construction market, and thus, by implication, support managed forestry. Old growth forest activists are not so agreeable, however. Modern Nordic managed forests have meant that only the surplus of any year’s growth is actually harvested, which is apparently quite enough, according to the Wood Town’s (see below) project architect Markku Karjalainen, who argues that potentially all Finland’s housing materials are grown every ten hours. Factor in the kinds of technologically-driven developments such as glue-lamination, along with a range of other innovations and one can see why some view companies and R & D as participating in developing some of the most advanced techniques – in industrial terms – for the application of timber technology to building in Europe.
It is only in the last ten to fifteen years, since the late eighties/early nineties, that timber’s relative gaping absence in the Finnish building industry has been belatedly recognised, along with the rediscovery of their major building resource on the forest doorstep. In these last ten years initiatives are beginning to bring together different segments of the building industry: architects, construction and timber companies, governmental agencies, and university wood research departments. The result has been a renewed R&D energy and various building projects aimed at reintroducing wood as a practical material, and raising its visibility for architects, urban planners and the construction industry alike. One consequence has been raising sustainability issues, and unsurprisingly, both new buildings and new wood technologies are marketed as environmentally benign. That said, sustainability feels, and this, to the outsider still remains surprising, as if it is markedly off the building map. Wood is in several showcase projects, such as the Lahti Sibelius Hall, which is attempting to bring international attention to Finnish timber innovation. Usually though projects are more regional in ambition, from some of the largest timber bridge projects in Europe to the national Wood Town programme. All of these draw on timber material’s research and innovation, a R & D programme which also includes a variety of new interior timber-based materials and joinery products. Christian Affentranger, author of New Nordic Timber Architecture, notes in one of his chapters how across the Nordic timber building scene there is a divergence between a local timber traditionalism, which continues what has been learnt over the centuries in contemporary form, and the continuing development of new man-made composite timbers, which are being used in the most ambitious projects. This is particularly so with glue lamination, which enhances massive structures coming into the country, but the new thermowood, which is described below, is also the result of applying bio-chemical science to timber technology. How far this divergence will continue is one of the stories of the twenty-first century relating to the evolution of timber as engineering technology. Whether it is genuinely in the character of wood to actually do these things, is a question posed by one of the many Finn’s I talked with while in the country. But such nuances are not the concerns of the large companies and Governmental research departments propelling the research.
While Finnish timber building and architecture may not have arrived yet, they are approaching a crossroads. The core ingredients are present for significant change, notably in the abundance of wood. It will depend on architects, planners and the construction industry to build on the beginnings of the sea change already underway. Given regulatory demands, pressure to meet EU sustainability directives, and responses to environmental pressures in the coming years, the receptivity to a renewed Finnish regionalist wooden modernist aesthetic feels likely to make itself increasingly pronounced. With these sorts of thoughts in mind, the projects which comprise the remainder of this essay could be seen as harbingers of this change, rather than stand alone oddities.
Part 2: Four examples of wood build change
Up to 1997 a principal constraint for creating medium to large-scale buildings in wood were Finnish fire regulations. If the ratio of three or the maximum four storey domestic timberbuild housing sits at a low 2% of the total wood building stock it was even lower before 1997. In September of that year revised fire building regulations for any construction higher than two storeys, for the first time in over a hundred years, began to allow three or more storey timber-build to be recommenced, with new safety stipulations. The new regulations include sprinkler systems ensuring an hour’s fire resistance, allowing time for people to escape, and flame resistant ventilation systems. Since 43% of the population live in multi-storey apartments, and three quarters live in less than five storeys, amongst the small but committed timberbuild community, the feeling is that this is a rich opportunity for development. If the country was minded to, it could easily turn its residential building over to wood materials.
Oulu is far up on Finland’s north-east coast, far from the countries south-east post-industrial hub. It is also home to the most vibrant electronics and computer research and products’ economy, outside the gilded south-east. Oulu is one of the largest regional cities for people moving from the forested countryside. New homes are needed, and it is because of this need that one of the most significant wood projects in recent years, the Oulu Wood Town, has grown. The Wood Town was completed during the first half of 2002, but it began in 1995 as a student project, and developed an open competition for architects The final result was a completely urban district designed around wood.
Oulu’s wood town turns out to be a core, seven block area of housing, in the suburbs of the city, a ten minutes’ journey from the centre. It claims to be part of compact city thinking, a town-like environment, rather than a fully-fledged wood town. Upon arriving, I found myself reflecting on the multiple versions of compaction. Certainly, within the Finnish context, it is a leading example of sustainable thinking. Considerable play is made of both the use of wood, the high density of the buildings, and the development of three or four storey timber housing. The development is over twelve hectares or 20, 000 sq metres, and consists of eight three storey, and 70 other timber buildings, with about half rented and the other half owned, so as to ensure a mixed social balance. The project, instigated by the University’s Vice Rector, inaugurated a completely new Finnish focus on researching and then designing wooden apartment buildings which take advantage of the changes in fire regulations. After first apartment and the initial masterplan had been developed by students from the architecture department the site was handed over to a number of architects, who in turn became project designers for the further six areas of the site.
Visiting the site, in deep winter snow, it is quickly clear the buildings are low-key social housing, hardly the charismatic high profile projects, which grab the attention of the international architecture media. Today, on the ground, six differently designed building sections have been completed, housing 450 people. Within the different architectural styles some of the buildings make an effective case for a renewed timber functionalist aesthetic, alongside others which are visually indifferent housing. The two project managers refer vaguely to the Wood Town project, being part of a new timber building movement, but do not elaborate on whether this is formally acknowledged or just a piece of throwaway terminology.
What the two project architects, Markku Karjalainen and Ristu Suikkari, do elaborate on is how such a housing model is preferable to the concrete apartment high-rise which so many Finns continue to live in. Using surveys, interviews and questionnaires, the pair found that the majority of those asked wanted to live in wooden residential districts, with higher density, though smaller human-scaled houses with backyards, rather than in flats. All this is innovative in the Finnish context, although it harks back to the traditional vernacular urban wooden buildings which existed before the coming of concrete. In the Oulu example the project team have created narrow alleys between the blocks, without car access, for children to play and people to meet, an innovation in a modern Finnish urban design used to planning with space. The connecting walkways and alleys between buildings are small by comparison with the open spaced functionalism of the post-concrete urban planning, to convey intimacy. Building heights have also been varied. The architects at Oulu claim a significant influence from the remaining medieval districts of regional towns such as Porvoo and Rauma, where close, varied, vernacular buildings are still clearly evident.
In comparison with concrete, these multi-storey timber buildings are a new building type for the Finnish construction industry. During planning, while looking for the necessary skilled work force to construct the building, Karjalainen and Suikkari found the relevant skills and knowledge were on the verge of extinction. Handcrafts were part of building until the 1950’s, but quickly faded away as a living skill during that decade. For the wood town projects there is considerable prefabrication, but nonetheless a degree of retraining was needed. Karjalainen and Suikkari, therefore had to initiate training and courses with retired carpenters for a new generation of architects, engineers and builders to relearn forgotten skills for designing and constructing the timber the buildings. The two architects had to set up on-site training areas to reacquaint builders with the necessary skills. Karjalainen adds, ¨We have the material, we have the tradition, and now again we have the skills, after having lost them¨.
With timber factored into the dwelling density experiment a sustainable dimension was added. Other natural materials are used in construction, such as linseed paints, which are cooked onto the side of the walls. The results are houses in yellows, creams, reds, greens and greys, the latter ironically only too reminiscent of the dispiriting concrete colourings these buildings are seeking to replace. From the Oulu Wood Town model there’s been a mushrooming of interest around the country, with at least twenty other wood town districts in various stages of planning and completion, including a second in the Oulu district. The managers would like to have seen this in a central city site, as infill, but to their disappointment it has also been allocated a suburban position. Other projects include ones at Mikkeli, Porvoo, Lahti and Vantaa, all towns of some size.
To a certain extent one can imagine the concept of timber building as compatible with British concerns. Urban district ideas such as Oulu fit snugly into compact city theory, currently much beloved in Britain by the Urban Task Force and planners alike. Timber adds a another option to the sustainable palette. Given the renewed interest in wood as a building material in Britain, and the need for imaginative compact thinking, this double-win environmental fusion could well be cultivated here, just as in Finland. At a RIBA timber seminar two years ago, Maxwell Hutchinson mused on wood as the new glass. But whether planners here, in neo-tudor timber-frame Britain might experiment with such a wood-based functionalist aesthetic is an open question. According to Karjalainen, persuading their town planners and a conservative building industry was difficult enough. Many architects pointed out that the buildings looked too similar to concrete buildings. But Karjalainen comments these were the first in the rolling projects which have now taken off in many towns around the country. ¨It is growing, and we are learning¨, he remarks.
As the architects involved have developed a significant knowledge base in regard to timber construction, there is much to build on. If there is a groundswell of interest in the possibilities afforded by timber amongst architects, and, because of changing regulations, to the construction industry as well, the degree to which the project has been successful can be determined by future building It has been successful, in that around another twenty projects, either completed or under construction, have flowed from this initial research venture. But these are universally in smaller towns, and urban areas. The larger “stone cities” as Suikkhari calls them, have not been interested. There were no replies from two of the big four Finnish cities, Tampere and Turku, grist to his contention that there is an anti-wood bias. It’s also noticeable that Helsinki’s feted Arabianranta Virtual Village development, didn’t feel any need to integrate timber for any but the most decorative of functions. Still the increased interest in wood as material has meant there has been a reassessment in concrete and brick led construction circles as to the merits of timber, even though they returned to the primacy of their material choices. In this context the wood town project is something of a good news story for a country which had almost lost its timber tradition. While investment in a new generation of timber buildings is part of governmental strategy Suikkari points out, there’s a world of difference between celebrity timber buildings – for instance, the striking Sibelius concert hall – to what is surely the primary building type; our dwelling places. And the trend in Finland is away from the multistorey concrete apartment flats. Policy studies have recognised that the country has the highest number of people living in flats, around 500, 000 more than any other European country. Smaller lower storey residential houses are the homes of the future, which to a certain extent will include three and four storey timber build, though also, where possible, more single and two storey housing.
Joensuu is another city with wood town projects. Deep in the east of the country, known as Karelia, it is in yet more deeply forested country. It also happens to be one of the most economically deprived regions of the country. Forty years ago the regional population was a quarter of a million; today it is closer to 170, 000. Each year another thousand move from these rural districts to the thriving south and south east and to Helsinki, which is notÂ surprising since unemployment is running at 20%. As with so much of the north, the rural population is fast disappearing. The kind of forestry which remains mixes a high proportion of privately owned forestry with the big industrial forestry players. A depressed economy and the heavy and continuing westward migration are common factors which affect the forestry planning for the whole of the Eastern rim of the country.
On the train and bus between Oulu and Joensuu, through the backwoods of Finland’s far east, you cover hours and hours of forest. In point of fact, outside the towns, pretty much wherever you are travelling, the trees are there. The trees are not only central to the landscape, they are also central to the economy. If you travel on many of the passenger trains it will be an unusual journey, if you do not see the seemingly endless timber goods trains, laden high, with truck after truck of raw, recently-felled logs. On the bus journey to Joensuu we passed a stream of logging trucks heading in the opposite direction. Wood remains at the heart of this part of Finland.
Here any form of wood innovation which is a potential commercial winner is welcome. The story is well known. Effective timber innovation brings successful businesses, which bring money into the regional economy, which brings work and employment. Joensuu University includes a number of centres devoted to forestry and timber. Plans are already well advanced to build the largest multistorey timber building in the country on the campus, beginning in 2003. In such a context the development of any technological timber materials are seen as crucial, any criticism irrelevant.
This is exactly the situation with ThermoWood, essentially an environmentally sensitive form of heat treating and thus useful for modifying the construction potential of softwoods. A wholly industrial process, Thermowood was developed by the building technology arm of VTT, the Finnish Forest Research institute, before being launched into the marketplace in the last couple of years.
Today, three years on, there are a handful of companies who are expanding rapidly with this new modified wood. However you may feel about its mechanical preparation, and what it does to the wood, within the mainstream building community it is seen as an environmental step forward which avoids the hazards of toxic coatings previously necessary to get the same level of weather protection and durability. One consequence is that uncoated softwood can be used for external applications, including cladding and other surface features. Although it resists decay and is dimensionally stable Thermowood is limited in that ground-exposure is best avoided because of the high risk of rotting. Thermowood’s use has been growing rapidly over the last couple of years, with significant export pushes for all the companies involved. These include Stora Enso, Stellac who have their own brand version, Stellacwood, Ikipuu who are owned by Finnforest, and a number of small mills which produce around a 1000 million cubic metres a year. Thermowood’s intensive marketing across Europe comes hard on the heels of other forms of industrial wood interventions, not least Finland’s already established Kerto, and Wisa plywood products, as well as the increasing versatility of glulams.
One of these companies, Ikipuu, is about half an hour from Joensuu, and is perceived regionally as a significant entreprerneurial venture. The sawmill sits alongside two other company mills, in a sort of forest industrial park. Surrounded by trees, with trails leading off into the woods, the Ikipuu plant is growing and plans an increase in production over the next twelve months. The brand new factory, with its gleaming oil run heat kilns, alongside a careful computer controlled console to ensure the heat settings don’t go awry, looks to the untrained eye as if it is at the cutting edge of wood-computer technology symbiosis. The kilns were originally developed and manufactured by VTT – although there are now 3 or 4 producers. This kiln uses oil as fuel, although the manager was looking into a bio-boiler, which is wood based. A probe in the wood reads the materials’ parameters and determines the level of heat needed, all maintained within the equivalent of a robot workers’ database. Since the three main operating staff are linked up to their computers at home, they can modify the parameters as and if required from home, or if anything goes amiss can drive in speedily: this look like nothing else but hi-tech forestry. But such idle thoughts are summarily dismissed by the plants’ managing director, who appears to think the setup isn’t anything particularly special.
The Thermowood process is essentlally a mechanical form of drying the wood out, using a steam boiler (the steam protects the wood from igniting and other defects), while at the same time minimising energy consumption. The wood is first dried at between 100 and 130 degrees centigrade, to a moisture content of 3 or 4 degrees, for up to forty hours. It next rises to between 190 and 220 degrees, for an intensive period of between one to five hours. The maximum temperature depends on use – for instance for flooring and kitchen the temperature needs to rise to an intense 212 degrees. There is a very small shrinkage and swelling as a result of the high temperatures. After this the temperature begins to drop, and steam cools and remoisturises the wood, actually returning it to a higher moisture content than otherwise possible. Without this stage the wood would be very brittle. Different moisture regimes are used depending on whether thermowood is being prepared for cladding, exterior decks or sauna’s.
Seven principal benefits can be identified: the moisture content of the wood is reduced by 50%; a uniform colour throughout is created; the bending strength is decreased by between 10 and 30%; the maximum shrinkage and swelling reduces by 30 to 90%; there is an improved knot resistance for the wood without chunks; water absorption is reduced by 50%; and finally there is improved weather resistance.
All species of woods can be used, as well as sawdust and woodchips. With birch the process takes about 52 hours. The main two hardwood competitors are Western Red cedar and Siberian larch, and although Thermowood isn’t as beautiful it can do the same things, and, as it promoters never tire of telling people, much more economically. Making the Thermowood decision is being pitched as an ecologically friendly choice.There are many elements which make it far more environmentally friendly than other materials, including the capacity to recycle lowgrade chipwood with the steam boiler, thereby minimising energy consumption.
Across Europe variants on Thermowood process are beginning to be marketed; in Germany vegetable oil is used, and in the Netherlands cooking greenwood at high pressures, which is then cured is also practiced. Different companies have different standard sizes, but at present all the Finnish wood companies are keen to break into the British market. There are technical problems, from unresolved rotting; and health hazards, where water leakages have been identified though microtoxic tests show, so far, that these do not contain dangerous substances, and are considered harmless; to lesser difficulties such as nail stains and nail damage, though that could also be resolved by using stainless steel nails. In addition to these issues, Thermowood’s steam heat treatment makes for an attractive darkened finish, although the wood also requires surface treatment to withstand vulnerablity from ultraviolet rays.
An understanding of the possibilities in Thermowood has begun to move westwards from the Baltic, turning up in a variety of British architectural magazine features, often as adjunct to pieces about the recent cylindrical McDonald’s building situated on one of the main traffic arteries in and out of Helsinki. The McDonald’s building, designed by the Helsinki practice, Heikkinen and Komonen, to emulate a modern gateway at the city’s edge, is highlighted by an outer protective Thermowood skin of slats from head to ground level. Despite its dramatic appearance it is essentially a chunky concrete cannister, with the ornamentation of wood feeling like a sop to the locals from the kitchens of the American fast food industry.
Even if the building’s updated neo-modernism makes it an interesting building, and one which has won awards for the architects, as well as prestige for McDonalds’ it is far removed from sustainability. The Thermowood is a surface facade feature, which one suspects was chosen as much for promotion as for its environmental features. More promising is the other principal Finnish timber building which has succeeded in garnering a degree of attention beyond the immediate Nordic borders.
A brisk twenty minute walk along lake Vesijarvi’s shore from the centre of the country’s Southern city of Lahti, sits another showcase building, centrepiece to Finland’s efforts to fall back in love with timber. This is the Sibelius Hall, an impressive piece of modern engineering and architecture, combining a glass facade astride the updated brick shell of an original furniture factory, wood-welded together by massive glulam beams, which in turn join the third section, a wholly discreet inner philharmonic sanctum, to create a completely self-enclosed concert hall. In Finland it is a definite showcase, the first public timber building of significant size and scale for over a century. Funded in part by the EU, the original carpenters’ building which the hall has been built upon is in a rundown industrial outskirt of the city, known as Ankkuri, part of an ambitous local regeneration plan, to restoke interest in timber, both regionally and nationally. For many in the timber industry the belief is that Sibelius Hall represents a turning point in the fortunes of their material in large-scale ventures.
Strategically, it is thought, with this building the virtues and values of wood can be conveyed to the wider Finnish architectural and building world. “Look what we can do!”, the building proclaims.
Indeed the proclamation brings a hush to one’s voice, as one moves in the foyer space between the main glulam timber trunk pillars, rising from the floor, before their branch-like struts splay and climb up into the rafters. It is airy though, the beam and support scaffolding representing the inner envelope which comprises the aptly descriptive ‘forest hall’ – its outer envelope is glass. The whole foyer area is bounded on one side by a warren of offices retrofitted into the original carpentry factory, and on the other by the hermetically sealed concert hall, sealed so as to ensure the best acoustical results.
From outside, the building is a dense thick cuboidal shoebox, its walls rising high above any immediate neighbouring buildings. Because there is so much glass, and because it in part issues out of the all-brick building, it can be, and is, asked, whether the hall is a genuine wooden building. Most in the Finnish wooden timber industry appear to believe so, and it is being promoted as such, a celebrity timber building catapulted into the world architecture network with ambitions on claiming international attention. In September 2002 it played host to the Finnish ‘Wood in Culture’ Association building awards, set up to promote the use of wood in building and to revive the country’s lost carpentry skills.
The Concert Hall is the result of a two-stage all European architectural competition, begun in the summer of 1997, and whittled down to three finalists by spring the next year. The winning design comes from two young architects, Kimmo Lintula and Hannu Tikka – part of a mainly Danish based practice and Artto Palo. Rossi Tikka, with limited experience in timber building. Construction was begun soon after, in August, 1998, and, with a hurried timetable, the building was complete in February 2000. Unsurprisingly the building demanded exacting acoustics, which turned out to require the main research effort. Working with VTT’s acoustical labs, the outer wall structure has been designed to provide the principal acoustic insulation – timber is so acoustically lightweight, absorbing as much external noise as possible through reverberation sensitivity, as well as the internal sound being reflected from inside the hall. Apparently for the first time in Finland, applying prefabricated massive solid and timber walls, the team constructed a multi-layered facade. An outer glass skin hangs from the roof with aluminium and wood beam supports. The inner concert hall walls sit at a slight angle. The architectural team, working with the VTT labs, developed narrow wall chambers with tightly packed sand particles, sandwiched between 9 metre by 1 metre kerto. The sand particles vibrate, dimming and insulating any sound. Along with these demanding conditions there are kerto walls, wisa plywood with a layer of mineral wool added to the insulation. This is a technique usually applied to concrete buildings, and it was initially unclear whether the acoustical specifications could be met. But, in fact, it turned out the wood and sand grain combination worked well, producing no discernible frequency vibration.
The other main research focus was in the jointing system and the development of the tree line gantry of beams and joists. Each of the three competition finalists had already been invited on a fact-finding visit to a number of middle European countries, checking out jointing systems. In Switzerland, Lintula and Tikka came across a working system which was already evident in a number of traditional buildings. Back at their architectural base the two applied, computer 3D modelling to enable them to figure out exactly how the joint, beam, and girder structures would work. Nine glulam spruce columns hold the roof structure, along with the foliage branching, and the three foyer levels are supported by additional horizontal heavy glulam beams. The actual work was almost completely pre-fabricated, most of it locally in Lahti, one of the country’s traditional centres of wooden furniture-making and design. The glulam tree trunk pillars were shaped 600 km’s further north, in a hi-tech but apparently very cold barn. Because of time and budgetary constraints particular effort and expertise was reserved for only some of the construction detail. Even so, because of the showcase nature of the project, a variety of woods were used, from Wisa Facade exterior plywood, stained to an oak finish, to lacquered birch-faced plywood doors for the reverberation chambers. Carpenters were brought in to concentrate on some of the finishings, ranging from walls, floors and also foyer furniture “this last a marketing extra emphasising the connection to the well-known and ongoing regional furniture industry.
Lintula sees the building as “honest – everything you see is how it’s meant to be”, which, with the large scale surface canvases suggests a definitely monumental quality, but also draws on the warmth of – thus the implicit overtones with classical music – as well. He also believes the building sends out the sustainability message loud and clear, but fused with varied innovations. Jointing and finishing, as found in the hall, and here is the irony, are all but alien to contemporary Finland. In a country with 23 million trees it feels strange that the Finns needed to go abroad to find solutions to realise this project. Much was learnt, both technically and in terms of fabrication, during the course of construction; the uses for imported machinery; the introduction of massive wall structures; new glueing techniques; and moreare presently seaping through as influences on Finnish architecture. “It makes you wonder” states Lintula, over the phone, weeks after my visits, “since it represents a generation who have not seen wood, how you can be ashamed of your roots and tradition, when you can have very beautiful results.”
A case for such new wooden public buildings is that they spur interest in the indiginous sustainable material, both for the public and professional architects alike. A case against is that in Finland most of the required stock of public buildings is complete, and these are principally concrete, and more recently brick, steel and glass, so there isn’t the need or opportunity for many new experiments in these building types. Lintula reports that there are plans for another large scale wooden public building in a town called Sovenlima. But this remains an apparently isolated development.
If examples are far and few between, one related by dint of its massive structure, though a thoroughly different building type, is the Vihantasalmi bridge, one of the largest wooden bridges in the world built for a main road. This imposing structure spans a watery lake expanse in Mantyharju, central Finland, 180 kilometres north of Helsinki. Up to the bridges inception only considerably smaller wooden bridges had been constructed in the country, so the Vihantasalmi structure is seen as a breakthrough for Finnish engineering. One of the most ambitious results in the second stage of the Nordic Timber Project, a programme which has been devoted to timber bridge research and construction during the second half of the nineties, the bridge opened in 1999. A highlight of the main Finnish contribution to the programme, with a specific emphasis on timber-concrete composite bridges, here the structure is divided into a three-span king-post truss comprised of load-bearing glulam beams and a wood-concrete deck. This form of construction is perceived and promoted as an environmentally responsible mode particularly as the wood is taken from locally sourced raw material. The total span is 168 meters, while the width of the roadway is 11 meters. and the sidewalk 3 meters,
The interest generated by the bridge meant that in 2000 it won Finland’s Wood Information award. The judges noted the revival in engineering structures employing wood as a primary material. Designed, after a competition which attracted over thirty entrants, by Insinritoimisto, Rantakokko and Co, the engineers used second order nonlinear theory for the structural analysis of the main load bearing system. This structural system, with each of the three main trusses 42 meters. apart, has antecedents in Finnish bridge building tradition but has been rendered realisable by the up-to-the minute technology.
These examples only scratch the surface of the annual timber build programme in Finland. But this programme in turn only scratches the surface of the whole Finnish building programme. Overall the industry’s mass production schedule, the priorities of the major builders and contractors is to produce houses, which while quite possibly using timber, are either complete or partial concrete frame designs. It is appealing to envisage Finland as a country where the mould might be broken because of the quality of the architecture and the living resources to hand.
If Finland were to break the mold with timber building, it might also break the mould of twenty-first century ecological architecture. Christian Afftentranger refers to the relation between tradition and modernity, in all Nordic timber architecture, drawing out the dynamic tension between the pull of tradition and the pull of modernity. The weighting of this balance – between modernity and tradition – also contributed to the Finnish architectural communities’ (reluctance to embrace the eighties and early nineties post-modernist boom. Where a neo-modernist style has continued to evolve, or even because the strength of resistance continues and refines the moment of modernism, a timber-hued gloss on this modernism sets up a similar alternative to Middle Europe’s eco-tech razzle-dazzle. If some of Finland’s mainstream contemporary avant-garde architecture refers self-consciously back to the themes of the twenties and early thirties, referencing the early work of Alvar Aaltoo as well as Corbusier, and placing it in modernism’s slipstream, a contemporary timber neo-modernism may be on the cusp of emerging, a separate movement to both the orthodoxies of tradition and the formal categories which are found in mainland Europe.