# Rotating timber planes define Japan's forest festival pavilion Temporary structure combines regional wood with innovative reuse strategy - **Source:** [architecture archives | designboom | architecture & design magazine](https://brifing.si/source/1e716da2-18e6-4704-96a6-818e7860b99f) - **Published:** 2026-09-05 - **Topic:** [Business](https://brifing.si/c/business) - **Original article:** - **On Brifing:** https://brifing.si/s/a13fcbf5-fb7a-4c3b-bdbb-9787e4472da4 ## Ceremonial forest architecture The Onodatesho Pavilion served as the ceremonial centerpiece for Japan's National Tree-Planting Festival, hosting the Emperor and Empress. This annual event since 1950 celebrates forest appreciation through temporary state architecture. Designed by Yano Aoyama Architecture, the 2023 pavilion in Ehime featured innovative timber construction. The structure traditionally gets dismantled after the day-long festivities, making material reuse a key design consideration. ## Innovative timber construction The pavilion combines regional cedar and cypress with cross-laminated timber (CLT) panels - the largest transportable in Japan at 12x2.3 meters. Instead of extensive cutting, designers used six geometric operations: tilt, rotate, lean, taper, shift and cut. A single joint detail repeats throughout the structure. This approach minimized material waste while creating the pavilion's distinctive three asymmetrical planes that rotate around an imaginary axis. ## Ceremonial design elements One wooden mass leans 10 degrees toward the audience, echoing nearby Mt. Ishizuchi's profile with slender steel rod supports. Plane positions considered ceremonial sightlines and sun protection needs. The arrangement symbolizes the festival's renewal theme: plant, grow, use, repeat. This thoughtful design integrates both functional requirements and symbolic meaning into the temporary structure's architecture. ## Regional collaboration Local carpenters, CLT manufacturers and drafters collaborated on the project, blending traditional timber techniques with modern production. Ehime-sourced cedar and cypress connected the pavilion to regional forests. The large CLT panels showcased local timber technology advancements. This cooperative approach supported regional industries while creating architecture deeply rooted in its location's material culture and craftsmanship traditions. ## Circular material strategy Cut-offs from primary CLT panels became secondary elements like stage stairs. After the festival, main panels can be unbolted for repurposing as school furniture. The design intentionally extended the materials' lifecycle beyond the temporary structure. This circular approach reduced waste while providing lasting community benefits - transforming ceremonial architecture into educational resources through thoughtful dismantling planning. ## Structural innovation The pavilion's three principal planes create dynamic spatial relationships through their rotations. Steel anchoring plates ensure stability while allowing for eventual disassembly. Light filters through the wooden slats, casting patterns that change throughout the day. These design choices demonstrate how temporary architecture can achieve both ceremonial grandeur and technical sophistication through innovative structural solutions. ## Cultural significance As the 76th iteration of this annual tradition, the pavilion continues Japan's postwar reaffirmation of its forest heritage. The National Tree-Planting Festival began in 1947 to promote reforestation. Each year's unique pavilion design reflects contemporary architectural approaches while serving this enduring cultural purpose. The temporary nature of the structures emphasizes renewal - a core theme of both the festival and sustainable forestry. ## Sustainable design legacy The Onodatesho Pavilion demonstrates how temporary architecture can model sustainable practices. Its material sourcing, construction methods and reuse plan create a closed-loop system. This approach influences broader architectural thinking about resource use, especially for event-based structures. The project shows how ceremonial buildings can lead rather than follow in environmental responsibility, setting precedents for the construction industry. ## Sources covering this story - https://www.designboom.com/architecture/temporary-timber-pavilion-cedar-cypress-reclaimed-clt-japan-forest-festival-onodatesho-yano-aoyama/ — --- _Summary written by Brifing from the original reporting. Copyright in the original article belongs to its publisher; read the full piece at the link above._