Farewell, Timber Utopia
Farewell, Timber Utopia
Returning to wood is not the architectural remedy I hoped it was
Dezeen recently concluded its fantastic series of reports on mass timber, the material widely touted as the future of sustainable architecture. I was reading closely, having welcomed the timber revolution myself a few years back.
Mass timber is the name given to structural building components made from engineered wood. Typically, layers of timber are glued together under high pressure, creating a kind of super-strong plywood which can be used for beams and panels. The appeal of such techniques, employed by numerous headline-grabbing “tall timber” structures in recent years, lies in their potential to reduce the enormous ecological impact of modern building. In particular, whereas the construction industry’s diet of concrete and steel accounts for around ten percent of global C02 emissions, timber buildings can, in theory, remove carbon from the atmosphere, since they lock-in the carbon captured by the trees that produce them.
For its more romantic supporters (myself included), mass timber also promised something more. It held out the possibility of rejuvenating a soulless, technocratic contemporary architecture, reconnecting it with the natural world and with the beauty of humanity’s most ancient building material.
Alas, I now think my enthusiasm was misplaced. The Dezeen series suggests mass timber is a promising addition to the architectural repertoire, but also drives home the dangers of expecting this technology to be transformative, which it won’t. The lesson here, it seems, is to be wary of solutions that promise to resolve the tragic complexity and dysfunction of the modern world.
The situation is laid out most starkly by the Austrian architect Hermann Kaufmann, who has been exploring wood construction since the 1970s. Kaufmann’s office building for the energy company illwerke vkw, on the site of a hydro-power lake in the Alps, was one of the buildings that awakened me to the possibilities of mass timber; it is an outstanding example of Modernism adapted to a natural setting, exuding an almost otherworldly serenity against its mountainous backdrop. But as Kaufmann points out, there are few places in the world where this kind of architecture can be adopted at scale, for the simple reason that few places have the requisite supplies of timber. Those forested regions cannot meet the material needs of the global construction industry, and certainly not if the goal is sustainability.
According to Kaufmann, the hype surrounding mass timber risks discrediting the technology. Besides the shortage of wood, there is a shortage of craftsmen who can build well with it. Modern societies no longer produce enough individuals with a deep knowledge timber construction, meaning that designs are often executed poorly. Then there is the inevitable problem of the mass timber label providing a green veneer for buildings that don’t actually contain all that much of it. As Kaufmann observes, “people will screw a couple of square metres of wood onto their facade and say the building is sustainable.”
The recently completed Ascent building in Milwaukee, Wisconsin, is a good example of mass timber meeting the realities of the real estate business. Looking at its generic glass and metal skin – requested by the property developer to maximise views – you wouldn’t even guess this is a timber building. Because it is a twenty-five story high-rise, the Ascent also needed a six story concrete base and concrete core to ensure stability and fire safety. It does contain a good deal of wood, but that had to be shipped from Austria, American supplies being too expensive.
This is not to deny the environmental advantages of mass timber, even in combination with other materials. The impressive Sara Kulturhus Centre in Sweden claims to be a carbon negative building, storing some 9,000 tonnes of C02 in its wooden mass, double the amount emitted during construction and enough to compensate for the building’s operation over a fifty-year lifespan. Thanks to its prefabricated components, mass timber also allows for fewer deliveries and faster building times, as well as a less noisy and toxic construction process.
But a handful of showpiece buildings does not amount to a timber revolution, at least as I imagined it. To capture the full potential of wood, I hoped we would do away with wasteful high-rises, replacing them with five or ten story structures whose demountable parts could be reused afterwards. I envisaged regions like Britain converting huge tracts of land to forests supporting softwood trees, the management of which would support a thriving rural economy.
To be sure, this vision was always a pipe dream, given the elaborate framework of subsidies, regulations and land allocation it would require. What I did not appreciate were the likely consequences of mass timber being widely adopted without that framework in place. Those consequences could be disastrous, with scarce forests being decimated for building supplies or replaced with ecologically barren timber plantations.
Such are the dangers of seeking big answers to big problems. Faced with a tragic conflict like that between an urbanising humanity and a deteriorating natural world, there is always a temptation to put our faith in a single speculative idea which might pay off at some point in the future. Not only do such fantasies bring unintended consequences; they give us an excuse to avoid dilemmas that, in reality, are not going away.
When it comes to the world’s huge appetite for carbon-intensive concrete and steel, there really is no obvious alternative to incremental improvements in green manufacturing and energy-efficient architecture. Sustainable alternatives like mass timber could be an important part of the puzzle, but likely a marginal one.
I don’t want to sound complacent about this: the situation is very depressing, and I hope I’m wrong about the lack of good answers. In the meantime, I hope we’ll see more mass timber. Even if it isn’t the breakthrough it’s made out to be, it’s still useful to have some illustration of what we are aiming for.