An architect named Michael Green believes he can make wooden skyscrapers that stand 100 storeys tall, and he's prototyping the idea with a 30-storey wooden building in Vancouver. More wooden high-rises are planned in Austria and Norway. Green uses laminated strand lumber, a glue/wood composite, and has char buffers to give it good safety in fires. He claims that his buildings can be cheaper than comparable structures made from traditional steel and concrete, and will have a smaller carbon footprint.
Wood buildings lock in carbon dioxide for the life cycle of a structure, while the manufacture of steel and concrete produces large amounts of CO2 -- the International Energy Agency (IEA) estimate that for every 10 kilos of cement created, six to nine kilos of CO2 are produced.
Green's "Tallwood" structure is designed with large panels of laminated strand lumber -- a composite made of strands of wood glued together. Other mass timber products use layers of wood fused together at right angels that making they immensely strong and able to be used as lode bearing infrastructure, walls and floors.
Despite being made of wood any worries about towering infernos should be banished, says Green, as large timber performs well in fires with a layer of char insulating the structural wood beneath.
"It may sound counter-intuitive, but performing well in a fire is something inherent in large piece of wood, that's why in forest fires the trees that survive are the largest ones," he says.