When it’s completed in 2041, it’ll be the tallest building in Japan and it’ll be 90 percent timber with some steel braces. If 2041 seems way in the future, there are some timber towers that have already been completed. There’s the Hoho tower set to be complete in 2019 in Vienna, 24 floors high and the Treet, a 14 storey all timber building completed in Norway in 2015. The reason for this tall timbermania, a convergence of environmental and demographic factors. First, there’s the biggie, a growing sense of urgency about climate change. The latest report from the United Nations Intergovernmental Panel on Climate Change says that to head off total climate disaster, we should limit the rise of global temperature to one and a half degrees Celsius. To do that, we need to cut our carbon emissions by about half by 2030. Over the past decade, some architects have started promoting timber construction as a carbon cutting solution.