Eye on 2×4: Addressing Labour Shortage & Improve Productivity on Job Sites in Japan

By: Kevin Bews

SPF Manager, Canada Wood Japan

Group photo of participants and images of wall and floor panels being delivered and assembled at the construction site (Photo credit: 2×4 Home Builders Association & Create Lemon Co., Ltd.)

Japan’s 2×4 construction industry is in the midst of a significant transformation, with an increasing focus on prefabrication. The rise in large-scale 2×4 construction projects highlights the need for improved efficiency and innovation. To tackle this challenge, a collaborative initiative is in progress, bringing together Canada Wood, COFI staff, the Japan 2×4 Home Builders Association, academics, and experts from the 2×4 design and building sector. Our collective goal is to establish unified standards and guidelines for prefabricating, transporting, and installing roof, wall, and floor assemblies in platform frame construction.

To test these new assemblies, Create Lemon Co., Ltd., a local 2×4 builder and component manufacturer in Yamagata City, and the secretariat for the Tohoku Branch of the 2×4 Association, is piloting a project. This project involves constructing two apartment buildings in Funagata Town, Yamagata Prefecture, to serve students, faculty, and staff of the Tohoku University of Agriculture & Forestry. On September 5, 2023, 26 individuals, primarily from the Tohoku Branch of the Japan 2×4 Home Builders Association and media representatives, visited the construction site to witness the progress of these buildings. The prefabricated floor and wall panel assemblies, including exterior wall assemblies with pre-installed insulation and windows, came together smoothly, aligning with the original design.

The Japan 2×4 Association, with around 750 housing and materials manufacturers, has been collaborating closely with industry stakeholders to establish and disseminate these standardized practices across Japan. According to Mr. Seiichi Sakaguchi, the association’s technical director, these standards will facilitate collaboration among different companies in designing and constructing large-scale and mid-rise 2×4 projects using prefabricated assemblies adhering to consistent 2×4 standards. This collaborative effort aims to increase awareness and interest among general contractors and government agencies in adopting this wooden construction method more widely in Japan.