Reusing and upcycling century-old beams could help fill the supply gap amid surging demand for timber products—expected to grow 49% over the next 25 years—and the drive for a fully circular economy.
It comes as Norway’s standards agency, Standard Norge, is drafting new standards (NS 3691-3) that will visually determine the strength of recyclable timber beams and provide a pathway for reusable structural beams in new projects. SINTEF, one of the country’s peak research bodies, is already testing century-old beams for reuse.
“We’re measuring applied force and deformations, which will enable us to say a lot about the strength of the beams”, according to Senior Adviser Sigurd Eide. “Many of them exhibit properties that are at least as good as new materials,” he said, adding that there are some characteristics that “can tell us a great deal about the strength of the timber.”
By and large, reusable beams are grey in colour and marked by the passage of time. Before testing the beams, researchers record any cracks or notches on the timber:
“We also measure the closeness of the annual rings and examine how the timber has been cut about the orientation of the grain in the wood,” Eide said. “Ideally, they should be cut parallel to the grain. The closer the alignment, the better. We also measure moisture content. We thus have quite a good idea of which beams are strong enough, even before we test them.”
The push to use more and more recycled timber comes as Wood Central reported that the FAO’s The State of the World’s Forests 2024: Forest-sector Innovations Towards a More Sustainable Future reported that demand for roundwood production might jump by as much as 272 million cubic metres per year by 2050.
Last year, Wood Central reported on emerging evidence that timber (specifically mass timbers) has a much higher recycling and reusable upcycle rate than ‘green steel’ and recycled concrete. At the same time, the market for reclaimed or recycled timbers has been identified as a growing market that meets the growing needs of construction—with Wood Central last year reporting that the market is expected to reach $74 billion by 2030.
