Backdrop & Context
Japan's stringent building regulations, particularly forwooden structures in a country prone to seismic activity and powerful typhoons,have historically limited the height and scope of timber construction. TheCzech Republic Pavilion breaks new ground by challenging these constraintsthrough innovative engineering and sustainable design principles. Thisachievement comes at a time when the global construction industry isincreasingly seeking alternatives to carbon-intensive building materials, withmass timber emerging as a leading solution for reducing embodied carbon whilemaintaining structural integrity.
"Wood has been used in Japanese construction forcenturies, but modern building codes have severely restricted its use in tallerstructures due to seismic concerns," explains Dr. Hiroshi Nakamura,structural engineering professor at Tokyo University. "What makes theCzech Pavilion so significant is that it demonstrates how advanced timberengineering can meet or even exceed the performance of conventional materialsin our challenging environment."
The pavilion's presence at the World Expo serves as apowerful demonstration of how traditional materials can be reimagined usingmodern technology to address contemporary challenges. With the constructionsector responsible for approximately 39% of global CO₂ emissions, according to theUN Environment Programme, the shift toward renewable building materials hastaken on new urgency.
Who's Involved?
The architectural vision came from Michal Gabaš, co-founderof Apropos Architects studio, who conceptualized the spiral structure as asymbol of societal and individual progress. "Eventually, we came up withthe idea of the spiral form of the pavilion, which symbolises a pathway forsociety or even for the individual," Gabaš explained to Radio Prague.
When asked about the inspiration behind the design, Gabašelaborated: "We wanted to create something that would not only showcaseCzech craftsmanship and innovation but also resonate with Japanesearchitectural sensibilities. The spiral represents continuous improvement,which aligns perfectly with both cultures' values."
Material suppliers played crucial roles, with Stora Ensoproviding 800 cubic metres of cross-laminated timber (CLT) and A2 Timber, StoraEnso's project partner, contributing over 200 cubic metres of glulam. Thetimber originated from PEFC-certified forests in Czechia, emphasizing theproject's commitment to sustainability throughout the supply chain.
Jiri Novak, CEO of the Czech Republic's Expo 2025Commission, emphasized the strategic importance of the pavilion: "Wedeliberately chose to showcase our expertise in sustainable forestry andadvanced timber engineering. The Czech Republic has a long tradition ofresponsible forest management, and we're now at the forefront of developinginnovative wood products for construction."
Engineering Challenges
Creating Japan's tallest steel-free timber buildingrequired overcoming significant regulatory hurdles. "The structure is onemajor challenge. Another major challenge is fire protection because the wholebuilding is made of timber. And the third major challenge is Japanese laws andbuilding regulations, which they require us to follow," Gabaš noted.
To secure approval, the design team had to conductlaboratory tests proving that both the wood components and their fasteningsystems could withstand earthquake forces and typhoon-strength winds. Thesetests were conducted at the prestigious Building Research Institute in Tsukuba,where the timber components were subjected to simulated seismic eventsequivalent to a magnitude 9.0 earthquake.
"The testing process was extraordinarilyrigorous," recalls structural engineer Jana Svobodova, who oversaw thecertification process. "We had to demonstrate not only that the structurewould remain standing during a major seismic event but also that it wouldmaintain its integrity with minimal damage. The natural flexibility ofengineered timber actually proved advantageous in absorbing and dissipatingseismic energy."
The successful test results highlighted timber's naturalresilience and flexibility during seismic events, qualities that have made it atraditional building material in Japan for centuries. The pavilion's firesafety strategy incorporated advanced intumescent coatings and strategiccompartmentalization to achieve the required fire resistance ratings withoutcompromising the exposed timber aesthetic.
Construction Process
The pavilion's assembly process showcased the efficiency ofmodern mass timber construction techniques. More than 50 shipments of Czechtimber arrived via Hamburg, with the entire timber frame erected in just threemonths. This rapid assembly timeline was made possible through extensiveoffsite prefabrication, where precision-cut timber elements were manufacturedto exact specifications before being shipped to the construction site.
Construction manager Pavel Dvorak described the process:"Each timber element arrived with a unique QR code that identified itsexact position within the structure. The digital model guided every step of theassembly, almost like a sophisticated puzzle. What would have taken a year withconventional construction methods, we accomplished in just over 90 days."
This approach minimized on-site waste and reducedconstruction time significantly compared to conventional building methods. Theexpedited timeline allowed ample time for the installation of the fully glazedspiral over the timber frame, completing the pavilion's distinctive appearancewell before the Expo's opening.
The construction team, comprised of both Czech and Japaneseworkers, developed innovative connection details to accommodate the building'sunique geometry while ensuring structural integrity. Custom-designed steelconnectors, though minimal in quantity, were strategically placed at criticaljunctions to transfer loads efficiently through the timber frame.
Architectural Features
The four-storey pavilion features a fully circular internalexhibition space measuring 402 square metres, divided into thirty-six equalsections using rational geometry. These sections are both structurallyfunctional and visually integrated into the building's overall aesthetic.According to Stora Enso, "The design concept, rooted in the principle ofraw material efficiency, ensures rapid on-site assembly using a mass-customisedcross-laminated timber kit of parts, Sylva™ CLT Walls and Floors by Stora Ensoand manufactured in the Czech Republic."
The building's spiral form creates a natural progressionthrough the exhibition spaces, guiding visitors through the pavilion's theme of"Talent and Creativity for Life." This spatial arrangement allows fora narrative experience that unfolds as visitors ascend through the structure,with each level offering new perspectives both of the exhibits and thesurrounding Expo grounds.
Interior designer Martina Novakova explains: "Wewanted the building itself to be part of the exhibition experience. The exposedtimber surfaces create a warm, tactile environment that contrasts beautifullywith the high-tech exhibits. Visitors can literally touch and feel thesustainable material that makes this architectural achievement possible."
The 12-metre crystal spiral, manufactured by the renownedCzech glass company Lasvit, serves as both a structural element and an artisticcenterpiece. The spiral's 1,200 individual glass panels, each uniquely shaped,create a dynamic interplay of light throughout the day, casting ever-changingpatterns across the timber surfaces.
Sustainability Considerations
Beyond its structural innovations, the pavilion embodiesprinciples of circular economy and sustainable design. "The design isoptimised for the easiest possible assembly on site and subsequent dismantlingafter the event," Stora Enso stated, highlighting the building's potentialfor reuse or recycling after the Expo concludes.
Environmental consultant Eva Horakova provides context:"The embodied carbon in this building is approximately 40% lower than anequivalent concrete and steel structure. Moreover, the timber itself storesabout 650 tons of CO₂ thatwas captured from the atmosphere during the trees' growth cycle."
The use of PEFC-certified wood ensures that the timbercomes from responsibly managed forests, while the carbon sequestered in thewooden structure helps offset the building's overall environmental impact.Unlike conventional concrete and steel structures, which generate significantcarbon emissions during production, the timber components actually store carboncaptured during the trees' growth.
The pavilion also incorporates passive design strategies tominimize operational energy use. The building's orientation and the strategicplacement of the glass spiral optimize natural daylight while controlling solarheat gain. A ground-source heat pump provides efficient heating and cooling,while rainwater harvesting systems supply water for landscape irrigation.
Cultural Significance
The Czech Pavilion stands as a symbolic bridge betweentraditional craftsmanship and cutting-edge technology. Wood has deep culturalsignificance in both Czech and Japanese architectural traditions, making it anappropriate material choice for this cross-cultural showcase.
Cultural historian Tomas Novak observes: "There's abeautiful symmetry in using timber for this pavilion. Both Czech and Japanesecultures have rich traditions of woodworking, from Japan's ancient temples toBohemia's timber-frame villages. This building honors those traditions whiledemonstrating how they can evolve to meet contemporary challenges."
The spiral design reflects the pavilion's thematic focus oncreativity and innovation as pathways to addressing societal challenges. As oneof the most visited structures at the Expo, the pavilion demonstrates howthoughtful architectural design can communicate national identity and valueswhile advancing global conversations about sustainable construction.
The exhibition spaces within the pavilion showcase Czechinnovations in fields ranging from nanotechnology to artificial intelligence,all presented within the context of sustainable development. Interactivedisplays allow visitors to engage with these technologies and understand theirpotential applications for addressing global challenges.
Key Takeaways:
• The Czech Republic Pavilion stands as Japan's tallesttimber building without steel supports, featuring an innovative 12-metrecrystal spiral design
• The structure contains 800 cubic metres ofcross-laminated timber from Stora Enso and 200 cubic metres of glulam from A2Timber, all sourced from PEFC-certified Czech forests
• Laboratory tests confirmed the building's resistance toearthquakes and typhoon-force winds, meeting Japan's stringent buildingregulations
• The timber frame was assembled in just three months aftermore than 50 shipments arrived via Hamburg, demonstrating the efficiency ofprefabricated mass timber construction
• The four-storey pavilion features a 402 square metrecircular exhibition space divided into 36 equal sections using rationalgeometry
• The design prioritizes disassembly and reuse after theExpo, exemplifying sustainable building practices and circular economyprinciples
