SENZOMATIC Humidity and Moisture Monitoring: How the Czech National Pavilion Coped with Osaka’s Climate
Throughout the duration of the event, the Czech National Pavilion at the World EXPO 2025 exhibition in Osaka, Japan, was equipped with the SENZOMATIC monitoring system, which continuously tracked the humidity, moisture and temperature of the wooden structure and its interior.
Not only the wooden structure of the Pavilion but also the exhibits on display require a stable environment with safe humidity levels. One example is the functional, actively used Petrof piano, which depends on consistent climate conditions. Wooden musical instruments are particularly sensitive to fluctuations in humidity — such changes can cause damage or require frequent tuning, while excessively low humidity can also be harmful. To prevent such issues, continuous environmental monitoring was implemented in the area where the instrument is located.
Although the outdoor relative humidity fluctuated between 35% and 95%, the humidity at the piano’s location remained within a stable range of 40% and 70%. Here again, the SENZOMATIC system played a key role, helping to maintain conditions that protected not only the Pavilion’s wooden structure but also the sensitive exhibits and valuable equipment inside.
Graph: Outdoor relative humidity RH (green) and humidity in the piano room (brown).
The construction of the Czech Pavilion presented a significant technological challenge. The EXPO 2025 site is located on an artificial island with a high groundwater level and close to the sea. Understandably, all stakeholders were keen to see how the wooden structure would perform in a coastal environment.
The local conditions posed specific risks for the Pavilion:
- High air humidity in Osaka’s subtropical climate, commonly ranging between 70% and 85% in summer, significantly higher than in Central Europe, creating a real challenge for wooden structures and interior furnishings.
- Strong ocean winds, which increase structural load and promote moisture penetration in detailed elements.
- Heavy downpours.
- Significant temperature fluctuations between hot and cooler periods, which can lead to the formation of drying cracks.
Data confirms the durability and quality of the structure
Despite these climatic challenges, the data from the SENZOMATIC monitoring system produced highly positive results, alleviating initial concerns:
- After adapting to the local conditions, the wood’s moisture content stabilized at a safe 11% – 16% WMC (wood moisture content), well within acceptable limits for long-term structural exposure.
- Although outdoor conditions remain highly variable, the indoor climate of the pavilion is stable, with the building’s structure effectively compensating for fluctuations in the external environment.
These results confirm that high-quality Czech materials, combined with precise construction techniques, can withstand even extreme environmental conditions.
Graph: Moisture content of the wooden structure in different locations of the building
The example of the Czech Pavilion highlights an important point: monitoring the moisture content of wooden buildings is now an integral part of modern construction. In large, multi-storey residential buildings, for instance, it is essential to track moisture, humidity and temperature not only within the structural elements, but also in individual living units.
Micro-leaks pose a serious risk. Undetected water infiltration can cause hidden damage that only becomes apparent after months, often in the form of mould, material degradation, or structural weakening. Early detection is therefore critical.
Prevention instead of costly repairs
Regular monitoring enables even the smallest anomalies to be addressed in time. Preventive measures are always far less expensive than repairing long-term damage caused by excessive moisture. The SENZOMATIC system is therefore not merely a technological accessory, but an essential tool for protecting investments and extending the lifespan of buildings.
