After several decades of steering clear of buildings constructed with wood, wooden high-rises are making a comeback in the 21st Century. At the forefront of the movement to return to wood is the W350 “plyscraper” – a skycraper made of plywood – that is being planned for construction in Tokyo.
Earlier this month, Sumitomo Forestry Co. announced in a press release its plans to construct the world’s tallest wooden skyscraper to commemorate the company’s 70th anniversary. The plyscraper, which is being called the W350, is planned to be 350 meters (1,148 feet) and 70 storeys high and is slated for completion by 2041. The company has projected a cost of 600 billion yen ($5.6 billion) and plans to use it for commercial, residential, and hotel use as well as office space.
What stands out about Tokyo’s proposed plyscraper project is that 90 percent of the building will be constructed with wood while the remaining 10 percent will be made of steel. The interior of the W350 will be built with pure wood, according to the company’s press release, and the exterior will feature a wood-steel hybrid. The plans for the wood-based structure are following suit and expanding on a bill passed in 2010 requiring all buildings three storeys or less to be built with wood in an attempt to encourage the usage of more natural materials and prolong sustaining the country’s luscious forests.
Sumitomo Forestry Co.’s usage of wood stems from the material’s environmental sustainability. According to the company, the W350 wooden exterior will increase carbon fixation in the air and, with an increased demand for wood as building materials, will sustain the growth of Japan’s forests by utilizing its supply of wood. The fact that the Japanese government is encouraging the usage of wood in construction suggests a return for the material in buildings. But this begs the question as to why there was a move away from wood in the first place.
Across the pond in the United States, in 1871, the Great Chicago Fire razed almost the entire city to the ground despite the fact that many of Chicago’s buildings had steel-reinforced structures. More than 100 years later, the Grenfell Tower in London also went up in flames after a small fire began with a refrigerator in one housing unit, spurring a conversation around the safety of high-rise buildings in cities around the globe.
The return of wood as a popular building material is partially due to wood engineering technology, which has modified the structure of wood to make it just as robust of a material as steel or concrete. Cross-laminated timber, for example, is the gluing of multiple planks of wood to reinforce the wood’s strength, making it similar to the strength of steel. Alternatively, wood can also be used in construction in ways that steel and concrete cannot, simply because wood has a degree of malleability to it that the former do not.
While the W350 is attempting to be the world’s tallest wooden-structure, it definitely is not the first. In 2017, Vancouver completed the ‘Brock Commons,’ an 18 storey student dormitory made of wood while a 300 meter (984 feet) wooden skyscraper was planned for construction in London in 2016.