Weeks after the Brisbane Olympics organisers revealed their venue and infrastructure plan for the 2032 games, a team of Australian engineers, developers, and architects will today tour Ajinomoto, Japan’s National Stadium—home of the 2021 Olympics and the first timber-and-steel-framed stadium built for an Olympics in decades.
Led by Andrew Dunn, CEO of Australia’s Timber Development Association, the delegation will spend the week in Japan, where they will learn why Japan is a culture built with wood rather than stone and bricks. Today’s highlights include a 90-minute ‘VIP’ tour of the 68,000-seat stadium, “namely the special timber-and-concrete composite roof,” Dunn told Wood Central from downtown Tokyo.
Designed by Kengo Kum and Associates, the stadium is built from reinforced concrete and steel and clad with cedar panels along the eaves of the superstructure. However, the roof design—featuring steel and latticed timber—is sure to attract interest from games organisers (as well as the Macquarie Point architects) who are looking at carbon-positive materials to deliver legacy projects.
Last year, Wood Central revealed that more than 20,000 cubic metres of timber from each of the country’s 47 prefectures feature in the stadium’s roof and cladding.
“The roof alone uses more than 7,000 square metres of glulam,” according to Yuichiro Shinohara, CEO and President of Shinohara Shoten, who supplied the timber that went into the lattice roof system: “In total, it took (about) ten months to manufacture the glulam and two years to construct the stadium, Shoten said, with installers working side by side with the general contractor to deliver the project on time.
Introducing fireproof laminated wood
“But before we visit Ajinomoto, we’ll also visit Jutec’s 8-storey mass timber building in downtown Tokyo,” Dunn said. The standout building, constructed to celebrate Jutec’s 100th anniversary (in 2023), uses fireproof laminated wood – an alternative to gypsum board certified as “fireproof” by Japan’s minister responsible for building standards.
Wood Central understands that the new product, marketed as FR Wood, is developed by making a thin layer of wood and injecting a flame retardant into it to create a cinder-proof layer. It is then placed in a kiln, tightly compressed, and dried to create a product with the same one-hour fire resistance as gypsum board before being glued together and a decorative material applied to the finish.
Touring the building, Dunn said the building uses a special beam system: “There are three layers in the beam, one is decorative, the second has a fire-retardant pressure impregnated layer about 50mmm and the third is a structural beam,” he said, adding that the structural beams is made from sugi Larch and the outer layer from Japanese Cedar.
Dubbed the trip of a lifetime for engineers, architects and developers who have an interest in wooden architecture, Dunn said the week-long study tour will delve into the rich traditions of Minka (Kominka) construction – exploring the intricate building methods that have defined the Japanese architectural identity for decades: “Visiting forests and fabrication facilities, we will understand traditional construction techniques from root to roof, including expert carpentry demonstrations.”
Please Note: Wood Central will exclusive coverage from the tour all week, and will tomorrow cover a visit to a state-of-the-art post-and-beam house production factory.
