The Timber Revival: A Short History

For most of human history, if you built anything more than a wall of stone or mud, you built it in wood. Timber was abundant wherever forests grew, it could be worked with simple tools, and it did something no other early material could: it spanned. A beam of wood laid across two posts makes a doorway, a room, a hall - and that simple post-and-beam idea, in endless variations, is the root of built structure across the world.

The traditions are extraordinarily rich. East Asia refined timber framing into high art: Japan's Horyu-ji temple includes timber structures that have stood for well over a thousand years, and the region's bracketed timber joints let builders raise multi-storey pagodas that survived earthquakes by flexing. Europe covered itself in oak-framed houses, halls and barns, their pegged joints still sound centuries on. And the Indian subcontinent has its own deep timber lineage - the interlocking timber-and-stone kath-kuni and dhajji-dewari construction of the Himalayas, prized for its earthquake resistance; the timber roofs, screens and framing of Kerala's nalukettu houses and its temples; and countless regional vernaculars that read the local forest and climate with great sophistication.

What all these share is that timber was not a compromise - it was the premier structural material, chosen for its strength-to-weight, its workability and its availability, and mastered over generations of craft. But the same history records timber's genuine limits, the ones that eventually opened the door to its rivals. A member could be no bigger than the tree it came from, which capped spans and heights. Wood decays if it stays wet, and it burns - and as cities grew dense, timber fires became catastrophes, the Great Fire of London in 1666 being only the most famous of many that pushed authorities to favour non-combustible construction. These were real problems, not prejudices, and they set the stage for the century in which timber would be pushed aside.

The industrial age gave the world two structural materials that seemed to answer timber's every weakness, and within a few generations they remade what 'proper' construction meant. Mass-produced steel offered enormous strength in slender members, arriving in predictable, certified sizes; reinforced concrete could be poured into any shape, was strong in compression, and could be made fire-resistant. Together they enabled the two defining structures of the modern city - the skyscraper and the long-span frame - at a scale sawn timber simply could not reach.

The shift was not only technical; it was cultural and regulatory. Concrete and steel were non-combustible, and after centuries of devastating urban fires that was an overwhelming argument. Building codes in many countries responded by sharply restricting the height and size of combustible - that is, timber - construction, effectively legislating wood out of the tall and large building. At the same time, the prestige of the new materials cast timber as old-fashioned: concrete and steel were the language of progress, of engineering, of the serious commercial and civic building, while wood was relegated to houses, barns and the small and the rural. An entire profession grew up trained overwhelmingly in concrete and steel, with timber a minor subject.

The retreat was real and, in its own terms, rational - the new materials genuinely solved problems timber could not, and they built the twentieth-century world. But it came at a cost we only fully recognised much later: the enormous carbon released in making cement and steel, and the loss of a whole culture of building with a renewable, carbon-storing material. For roughly a century, in the mainstream of construction, timber was the material of the small and the domestic, and the idea of a timber office block or a wooden high-rise would have struck most engineers as faintly absurd. That is the assumption the revival had to overturn - and to overturn it, timber first had to be reinvented.

The reinvention came, quietly, from the timber-rich countries of central Europe. In the early-to-mid 1990s, researchers and manufacturers in Austria (with work also in Germany and Switzerland) developed cross-laminated timber - gluing layers of boards at right angles to make a large, strong, dimensionally stable panel, in effect a structural plywood scaled up to the size of a wall or floor. CLT solved timber's oldest limit at a stroke: it could be made far bigger than any log, strong in two directions, precise and predictable. Combined with glulam, which had been maturing for beams and columns since the early twentieth century, it gave designers a full structural kit of parts in engineered wood.

Adoption spread outward from the Alpine countries through the 2000s, and then the story became a visible, almost sporting contest to build higher. London's Stadthaus at Murray Grove (2009) showed a nine-storey residential building could be built largely in CLT. Melbourne's Forte (2012) carried the idea to Australia. Then the numbers climbed fast: Brock Commons at the University of British Columbia (2017) reached eighteen storeys as a timber-hybrid student residence; Norway's Mjostarnet (2019) stood about 85 metres and claimed the title of world's tallest timber building; and Milwaukee's Ascent (2022) pushed higher still at roughly 87 metres. Journalists coined the word 'plyscraper' for these towers, and each one served as a public proof that engineered timber could do work everyone had assumed belonged to concrete and steel.

The race matters less for the records than for what it demonstrated and unlocked. Each landmark building forced engineers to solve real problems - connections, fire, acoustics, movement - and to prove the solutions to sceptical authorities, which in turn nudged codes to allow taller timber. The towers grabbed headlines, but the deeper revival is broader and quieter: thousands of mid-rise homes, offices, schools and civic buildings now built in mass timber as a normal, if still specialist, choice. India sits early on this curve - the material, the codes and the supply chain are still emerging here - but the global trajectory is unmistakable: in three decades timber went from banned-from-height to competing for the skyline.

A fair question is why the revival caught fire in the last two decades rather than, say, soon after CLT was invented. The answer is that three powerful forces converged, and it is their overlap - not any one alone - that made mass timber not just possible but urgent.

The first and deepest is carbon. As the world grasped the scale of construction's climate impact, and as operational energy got cleaner, attention turned to embodied carbon - the emissions locked into materials, and especially into structure. Cement and steel are among the largest industrial sources of carbon dioxide, released the moment they are made. Timber is the striking exception: grown by sunlight, it avoids those process emissions and stores carbon the forest captured. In a carbon-constrained century, a renewable, carbon-storing structural material stopped being a curiosity and became something the industry actively needed.

The second is prefabrication and productivity. Construction is famously slow, wasteful and short of skilled labour, and its productivity has barely improved for decades. Mass timber offers a way out: large elements are made precisely in a factory and assembled on site like a kit - fast, quiet, clean, with fewer people and less waste. For clients and contractors, that programme and site benefit is often as persuasive as the carbon story.

The third is technology. Mass timber is a child of the digital age as much as the forest. Computer-controlled (CNC) machining cuts complex timber elements and their joints to millimetre precision; building information modelling (BIM) lets the whole kit be designed, coordinated and manufactured from one model; and decades of structural and fire research and full-scale testing have produced the evidence that lets engineers design timber towers and authorities permit them. Without digital fabrication and that body of testing, the tall-timber race could not have happened.

Stack the three together - a material the climate needs, a process the industry needs, and the technology to make it work and prove it safe - and the timing makes sense. That convergence is why a course on mass timber is timely now, and why designers who understand it are positioned for the buildings this century will demand.