The world’s tallest hybrid-timber building recently received development approval

The technology behind it is surprisingly simple. The two main materials are glued laminated timber (glulam) and cross-laminated timber (CLT). The former is made from layers of lumber bonded togethe r, with the grain running in the same direction, giving it a higher load-bearing capacity than both steel and concrete, relative to its weight. It is ideal for columns and beams, and forms the structural bones of the cultural Centre, which is home to two theatres, a museum, an art gallery and a library. CLT, meanwhile, is like super-sized plywood, with each layer stuck at right-angles to the next. This makes it strong in all directions, so it is perfect for walls and floor slabs. The lift cores at either end of the 20-storey tower are made from CLT, with prefabricated hotel room pods stacked between them, incorporating glulam columns in their corners for strength. Finally, the double-skin glass façade keeps the rooms insulated in winter and cool in summer, as the warmed air rises between the panes of glass. The “self-finish” nature of structural mass timber, which can simply be left exposed, means that the tower was incredibly quick to build, doing away with the usual wet trades of plastering and decorating. A whole year was saved by using wood, compared with steel and concrete, with a storey completed every two days. The number of truck deliveries was also reduced by about 90%, with practically zero waste on site. Like bits of a giant balsa-wood model, the pieces came from factories ready to be bolted together, some in panels 27 metres long, while the trees were harvested from within a 60km radius of the site – and have all since been replenished. Just like the region’s forest-foraged restaurant menus, this is meaningful local sourcing rather than a green veneer. White Arkitekter carried out a 50-year lifecycle analysis that claims that Sara Kulturhus Centre will have a lifespan of at least 100 years. "In terms of lifecycle assessments, new trees have to be planted to replace the ones harvested for the cultural centre in order to be able to count as carbon sequestration," he continued. "New trees will grow during the building's lifespan. That is why we refer to the 50-year lifespan in our calculations." And to reduce the carbon emissions from the project's construction, locally sourced timber was harvested and then manufactured at a nearby sawmill. A geothermal heat pump and a large array of solar panels, in addition to sourcing energy from other renewable sources, are used to reduce the carbon emissions as the building operates. For more on this story, go to Dezeen .