JP｜EN
Development of New Wood Construction Methods Referencing Traditional Architecture
Life Cycle House
Background and Purpose
Today, there is a growing demand for comfortable built environments with minimal impact on the local environment. Wood, a renewable resource with low environmental impact, is one of the ideal materials. However, despite Japan's forests being rich in timber ready for harvest, the self-sufficiency rate remains low at around 30% (40% as of 2024). Against this backdrop, we aim to propose housing that maximizes wood's properties and is optimal for both people and nature. To achieve this, we are developing a structure that is simple to assemble and disassemble, minimizing the use of metal fittings and fossil fuel-derived building materials. This research aims to clarify the structural characteristics and environmental impact of the newly developed structural system.
Results
This study developed a processing system combining the traditional timber framing method with log construction. To verify the mechanism of shear resistance between logs—a key structural point—shear performance was analyzed in detail through element tests on joints, examining differences in shear keys. Simultaneously, based on a construction system that ensures precision using simple processing equipment, a model wall body functioning as a load-bearing wall was designed and its performance confirmed through full-scale testing. These results led to obtaining certification from the Minister of Land, Infrastructure, Transport and Tourism regarding the wall multiplier for timber post-and-beam load-bearing walls. Furthermore, the environmental benefits of this construction method were quantitatively demonstrated by comparing the carbon footprint during the material manufacturing stage with other common construction methods.
List of Research Topics
Master's Thesis
Development of a New Timber Construction Method Referencing Traditional Architecture -Multi-Criteria Evaluation of the Material Manufacturing Stage Using LCA-
Development of a New Timber Construction Method Referencing Traditional Architecture -Comparative Verification of Interlocking Joints via Component Testing-
Bachelor's Thesis
Considerations on Tiny Houses - Focusing on Cases Since 1990 -
Development of a New Timber Construction Method Referencing Traditional Architecture - Influence of Shear Plane Number Between Laminated Members on Structural Performance -
Development of a New Timber Construction Method Referencing Traditional Architecture Part 4 - Examination of Thermal Performance in Buildings Using the J-Log Method -
Development of a New Timber Construction Method Referencing Traditional Architecture Part 3 - Evaluation and Comparison of Carbon Footprints -
Development of New Timber Construction Methods Referencing Traditional Architecture Part 2 - In-Plane Shear Testing of Load-Bearing Walls Composed of Massivholz Panels and Framing Using Tongue-and-Groove Joints -
Development of New Timber Construction Methods Referencing Traditional Architecture - Shear Performance Testing of Load-Bearing Walls Composed of Log Construction Members Using Timber Connectors and Framing -
Peer-reviewed paper
・Takano A., Aiki M. . A Multi-Criteria Approach to Sustainable Building Material Selection: A Case Study in a Japanese Context . Sustainability17 (9) ( 4210 ) 2025.5
・Atsushi Takano, Masashi Aiki, Ryuto Yasunaga . Sustainable building material selection: A case study in a Japanese context . IOP Conf. Series: Earth and Environmental Science588 ( 022069 ) 1 - 4 2020.11
List of Awards and Honors
・Kitazono Lumber Co., Ltd., Tongue-and-groove laminated panel (90mm thick × 1790mm wide) composed of tongue-and-groove laminated lumber and four vertical battens / Screws STS6.5・F135 diagonally fastened / Panel-to-column joints @ 180mm, Panel-to-top/bottom horizontal framing joints @ 350mm / True Wall Specification / Wall Length 1900mm / Timber Frame Load-Bearing Wall, Japan Housing and Wood Technology Center (Public Interest Incorporated Foundation), 2021
