Maniwa: The Wooded City 蒜山・CLT建築物（美術館予定）：真庭市の木材利用を解説 （木材の特徴・日本の近代木造の特徴）

In the 1970s, the national forestry industry began to decline due to lower-priced imported wood and changing consumer preferences. To preserve the local industry, Maniwa began exploring new ways of making efficient, eco-conscious use of the lumber it produces—such as promoting the use of cross-laminated timber (CLT). This building was designed to showcase the attractiveness and versatility of CLT, which was developed in Europe during the mid-1990s.

The CLT production process involves forming large wooden panels by gluing sawn lumber planks together in perpendicular layers. The resulting material offers more stability, better fire resistance, and better insulation than standard wood paneling, and also retains the wood’s natural color and grain. Because CLT is made from a renewable resource, it provides an environmentally friendly alternative to concrete.

Trees cover about 80 percent of Maniwa’s land, and timber and lumber are key industries in the Hiruzen area. Tree species suited for commercial timber were planted extensively beginning in the late nineteenth century. At that time, felled trees were transported by river to the city of Okayama, but the opening of a rail line in 1936 turned Maniwa into a major timber supply base for the Kansai region. The main species grown for lumber are Japanese cedar, hinoki cypress, and pine.

Around 1975, the forestry industry began to suffer because of changing consumer preferences and an influx of cheaper imported woods. While Maniwa’s industry remained relatively strong throughout the 1980s, local business leaders sought to protect it by finding better ways to use domestic timber. They focused on sustainability, conservation, and the use of modern technologies for forestry management and wood processing. One such innovation that set Maniwa apart from other timber-producing areas in Japan was the adoption of a cutting-edge technique for drying harvested timber. Today, the city uses sensor-equipped drones and cloud databases to strategically catalogue and manage forestry resources, while also exploring new ways of making efficient, eco-conscious use of its wood—like technologies such as cross-laminated timber (CLT).

Developed in Europe in the mid-1990s, CLT has gained traction in Japan in recent years for its beauty and versatility. Production involves forming large wooden panels by gluing together thin planks in perpendicular layers. The resulting material offers more stability, better fire resistance, and better insulation than standard wood paneling, while retaining the natural color and grain of the wood. Because CLT is made from a renewable resource, it is an environmentally friendly alternative to concrete.

Scrap wood and sawdust from Maniwa’s timber industry are put to use for the good of the local community. Since 2015, the 78,000 tons of waste produced annually has been transformed into usable energy at Maniwa Biomass Power Plant. The plant produces 10,000 kilowatts—more than enough energy for the city’s 22,000 homes— and the surplus is sold to outside power companies.

Japanese architecture, whether traditional or modern, tends to incorporate minimalist design, lightweight materials, and porous boundaries between indoor and outdoor spaces. Wood has always been a key element, and the enduring connection to the surrounding forest can be seen everywhere in Maniwa. From historic structures like the graceful eaves of Fukuda Shrine to new buildings that incorporate the latest CLT technology, Maniwa is made from wood—and wood has made Maniwa.